Unified Circuit Research Articles

Quantum‐Enhanced K‐Nearest Neighbors for Text Classification: A Hybrid Approach with Unified Circuit and Reduced Quantum Gates

Quantum‐Enhanced K‐Nearest Neighbors for Text Classification: A Hybrid Approach with Unified Circuit and Reduced Quantum Gates

Midbrain lesion-induced disconjugate gaze: A unifying circuit mechanism of ocular misalignment?

Midbrain lesion-induced disconjugate gaze: A unifying circuit mechanism of ocular misalignment?

Living-Neuron-Based Autogenerator.

We present a novel closed-loop system designed to integrate biological and artificial neurons of the oscillatory type into a unified circuit. The system comprises an electronic circuit based on the FitzHugh-Nagumo model, which provides stimulation to living neurons in acute hippocampal mouse brain slices. The local field potentials generated by the living neurons trigger a transition in the FitzHugh-Nagumo circuit from an excitable state to an oscillatory mode, and in turn, the spikes produced by the electronic circuit synchronize with the living-neuron spikes. The key advantage of this hybrid electrobiological autogenerator lies in its capability to control biological neuron signals, which holds significant promise for diverse neuromorphic applications.

A method of power-electronized supply accommodation capacity analysis for receiving-end grid based on multi-objective optimization

Abstract With the development of renewable energy and high voltage direct current (HVDC) system, the proportion of power-electronized supply in power system is increasing. It creates challenges to the safe and stable operation of the receiving power grid. Reasonable evaluation of the scale of power-electronized supply that can be carried by the receiving-end grid is of great significance to guide power grid construction and maintain its operational safety. Firstly, this paper explains the theory that the unified effective short circuit ratio (UESCR) can reflect the static voltage stability of buses. Then, a multi-objective optimization model, which considers the external dc feed-in, local renewable energy, unit output, and operation constraints, is established to obtain the power-electronized supply accommodation capacity. And it is solved repeatedly by means of cyclic increasing dc feed-in scale and renewable energy penetration. Finally, the effectiveness and practicability of the proposed method are verified in a modified IEEE 39 bus system.

Feedforward mechanisms of cross-orientation interactions in mouse V1

Sensory neurons are modulated by context. For example, in mouse primary visual cortex (V1), neuronal responses to the preferred orientation are modulated by the presence of superimposed orientations ("plaids"). The effects of this modulation are diverse; some neurons are suppressed, while others have larger responses to a plaid than its components. We investigated whether this diversity could be explained by a unified circuit mechanism. We report that this masking is maintained during suppression of cortical activity, arguing against cortical mechanisms. Instead, the heterogeneity of plaid responses is explained by an interaction between stimulus geometry and orientation tuning. Highly selective neurons are uniformly suppressed by plaids, whereas the effects in weakly selective neurons depend on the spatial configuration of the stimulus, transitioning systematically between suppression and facilitation. Thus, the diverse responses emerge as a consequence of the spatial structure of feedforward inputs, with no need to invoke cortical interactions.

Quantum Circuit Rules for Molecular Electronic Systems: Where Are We Headed Based on the Current Understanding of Quantum Interference, Thermoelectric, and Molecular Spintronics Phenomena?

In this minireview, we discuss important aspects of the various quantum phenomena (such as quantum interference, spin-dependent charge transport, and thermoelectric effects) relevant in single-molecule charge transport and list some of the basic circuit rules devised for different molecular systems. These quantum phenomena, in conjunction with the existing empirical circuit rules, can help in predicting some of the structure-property relationships in molecular circuits. However, a universal circuit law that predicts the charge transport properties of a molecular circuit has not been derived yet. Having such law(s) will help to design and build a complex molecular device leading to exciting unique applications that are not possible with the traditional silicon-based technologies. Based on the existing knowledge in the literature, here we open the discussion on the possible future research directions for deriving unified circuit law(s) to predict the charge transport in complex single-molecule circuits.

Calculation of Earth Surface Potential and Neutral Current Caused by HVDC Considering Three-Dimensional Complex Soil Structure

In ground return mode of high-voltage direct current (HVDC) transmission, direct current is injected into the soil through a ground electrode, causing ground potential rise in different areas and direct current at the neutral point of transformers. Earth surface potential (ESP) and neutral current are closely related to the 3-D structure of soil, but few studies treat the soil three dimensionally when calculating these two parameters. In this article, a 3-D resistor network (RN) is developed to construct the soil model, and a soil–grid unified circuit model is proposed to simplify the calculation of neutral current. The RN method is verified by calculating ESP of a horizontal multilayer soil model and contrasting the result with that of CDEGS software. The feasibility and accuracy of the soil–grid unified circuit model is demonstrated through comparing neutral currents of two substations with the results calculated by finite-element method (FEM). The influence of resistivity changes in a water-bearing fault on ESP and neutral current is specifically analyzed using RN method and FEM to prove the necessity of considering the 3-D complex soil structure. The results of this article contribute to the simulation of DC distribution of wide-area HVDC transmission in complex soil structures.

Towards optimization of plant cell detection in suspensions using impedance-based analyses and the unified equivalent circuit model

An improved approach for comparative study of plant cells for long term and continuous monitoring using electrical impedance spectroscopy is demonstrated for tomato and tobacco plant cells (MSK8 and BY2) in suspensions. This approach is based on the locations and magnitudes of defining features in the impedance spectra of the recently reported unified equivalent circuit model. The ultra-wide range (4 Hz to 20 GHz) impedance spectra of the cell lines were measured using custom probes, and were analyzed using the unified equivalent circuit model, highlighting significant negative phase peaks in the ~ 1 kHz to ~ 10 MHz range. These peaks differ between the tomato and tobacco cells, and since they can be easily defined, they can potentially be used as the signal for differentiating between different cell cultures or monitoring them over time. These findings were further analysed, showing that ratios relating the resistances of the media and the resistance of the cells define the sensitivity of the method, thus affecting its selectivity. It was further shown that cell agglomeration is also an important factor in the impedance modeling in addition to the overall cell concentration. These results can be used for optimizing and calibrating electrical impedance spectroscopy-based sensors for long term monitoring of cell lines in suspension for a given specific cell and media types.

Aberrant dynamics of cognitive control and motor circuits predict distinct restricted and repetitive behaviors in children with autism

Restricted and repetitive behaviors (RRBs) are a defining clinical feature of autism spectrum disorders (ASD). RRBs are highly heterogeneous with variable expression of circumscribed interests (CI), insistence of sameness (IS) and repetitive motor actions (RM), which are major impediments to effective functioning in individuals with ASD; yet, the neurobiological basis of CI, IS and RM is unknown. Here we evaluate a unified functional brain circuit model of RRBs and test the hypothesis that CI and IS are associated with aberrant cognitive control circuit dynamics, whereas RM is associated with aberrant motor circuit dynamics. Using task-free fMRI data from 96 children, we first demonstrate that time-varying cross-network interactions in cognitive control circuit are significantly reduced and inflexible in children with ASD, and predict CI and IS symptoms, but not RM symptoms. Furthermore, we show that time-varying cross-network interactions in motor circuit are significantly greater in children with ASD, and predict RM symptoms, but not CI or IS symptoms. We confirmed these results using cross-validation analyses. Moreover, we show that brain-clinical symptom relations are not detected with time-averaged functional connectivity analysis. Our findings provide neurobiological support for the validity of RRB subtypes and identify dissociable brain circuit dynamics as a candidate biomarker for a key clinical feature of ASD.

Jerk forms dynamics of a Chua’s family and their new unified circuit implementation

A scheme to implement the Jerk form of the Chua system family using a controllable canonical form applied in linear systems is proposed. The main thought is that the nonlinear function with a single independent variable input can be superposed by a multiple linear function, which is regarded as the input of the system, and its single variable is regarded as the output of the system. Its state space could be reconstructed into the controllable canonical form. The output after transformation is fed back to the nonlinear function as its input independent variable, thus the controllable canonical form is transformed into the Jerk form of the Chua’s chaotic system. All Jerk forms of three-order Chua system, and part Jerk forms of four-order Chua system are presented. Analysis of the Lyapunov exponent spectrum, eigenvalues of the original three-order, four-order Chua systems and their Jerk forms, and the same values demonstrate the equivalent of the systems for both structures. According to the complexity and National Institute of Standards and Technology (NIST) test results, the pseudo-random performance of the chaotic sequence brought by the Jerk forms of the Chua system is better. The simplest unified circuit block diagram for the Jerk forms of the Chua’s family is also given. By changing their resistance parameters, the bifurcation diagrams show that Jerk forms’ systems are entering chaos, these circuits implement results of 2–6 scroll attractors. Experimental observations are provided for confirmation.

A Physics Based Unified Circuit Model for Single Photon and Analog Detector

Photodetectors having an internal carrier multiplication mechanism such as avalanche detectors and recently discovered detectors with cycling excitation process (CEP) have attracted tremendous interests for their high sensitivity and flexibility of being operable in analog, sub-Geiger and Geiger mode. Detection of single or few photons in Geiger mode or sub-Geiger mode is particularly interesting as LiDAR systems are finding a wide range of applications in autonomous driving, augmented and virtual reality, robotics, imaging, sensing, and communications. In this paper, we present a universal detector equivalent circuit model, applicable to all modes of operation, for photodetectors with carrier multiplication gain. The bias-dependent gain, bandwidth, as well as gain buildup dynamics are rooted in device physics and translated into an equivalent circuit model that can be readily incorporated into integrated circuit design. The model simulates the characteristics of devices biased below and above breakdown voltage, making seamless transitions between analog, sub-Geiger, and Geiger mode with the same set of parameters directly obtained from the material properties. As a result, circuit designers can choose detectors using different gain medium (e.g., Si, InP, InAlAs) to simulate device effects on system performance. The circuit model is implemented in Orcad PSpice circuit simulator. Its wide applicability is demonstrated by simulating the device in linear, sub-Geiger and Geiger mode with external amplifiers and quenching circuits, as well as the gain-bandwidth product of detectors with a Si and InAlAs gain medium.

EIS Investigation on the Influence of Natural Releasing of Inhibitor from Coral Aggregate on the Steel Corrosion in Coral Aggregate Concrete

Abstract Steel corrosion in coral aggregate concrete (CAC) mixed with different inhibitors was investigated using electrochemical impedance spectroscopy (EIS) technique in this paper. Considering the porosity characteristic of coral aggregate, a novel method of premixing inhibitor into coral aggregate was proposed and compared with the conventional mixing method for inhibitor. Three equivalent circuits were proposed and validated for the interpretation of EIS data of CAC. Finally, the influences of inhibitor type (calcium nitrite [CN] and amino-alcohol [AA] inhibitor), inhibitor content, and mixing method on the steel corrosion in CAC were analyzed and discussed through the EIS results. Results indicated that there were good fitting effects for the proposed circuits fitting the EIS data of steel in CAC mixed with different inhibitors. The anticorrosion effect of 3 % CN inhibitor is better than that of 2 % AA inhibitor in early phase (0–180 days), whereas the effect of the latter is more pronounced than the former in late period (180~270 days). In addition, according to the evolution of passive film resistance of steel in CAC, the premixing method is proven to be more effective than the direct-mixing method in long-term anticorrosion work. Finally, a unified equivalent circuit was established to interpret the EIS data of CAC, which has a promising significance in the further investigation of steel corrosion in CAC.

A Topology Synthetization Method for Single-Phase, Full-Bridge, Transformerless Inverter with Leakage Current Suppression Part I

Single-phase full-bridge transformerless topologies, such as the H5, H6, or the highly efficient and reliable inverter concept (HERIC) topologies, are commonly used for leakage current suppression for photovoltaic (PV) applications. The main derivation methodology of full-bridge topologies has been used based on both a DC-based decoupling model and an AC-based decoupling model. However, this methodology is not suited to the search for all possible topologies, and cannot verify whether they are inclusive. Part I of this paper will propose a new topology derivation methodology based on unipolar sinusoidal pulse width modulation (USPWM) to search all possible full-bridge topologies for leakage current suppression. First of all, a unified circuit model is proposed, instead of the DC- and AC-based models. Secondly, a mathematic method called the MN principle is then proposed to search for all possible topologies, and a derivation procedure is provided. It was verified that all existing topologies could be found using the proposed method; furthermore, seven new topologies were derived. The proposed topology derivation methodology is extended to search topologies under Double-Frequency USPWM (DFUSPWM). Twenty topologies under USPWM and four topologies under DFUSPWM have been derived.

Особенности распределенного хранения медицинских изображений в онкологической службе в рамках создания единого цифрового контура

The development of an effective unified information space of the regional radiology diagnostics service is possible by connecting all outpatient cancer care centers and medical organizations to distributed medical image storage systems under the management of regional radiological information systems within the framework of the regional programs “Creation of the unified digital circuit in healthcare based on the unified state health information system” of the territorial subjects of the Russian Federation. The aim of the research is to study the features of using radiological information systems in the oncological profile and develop recommendations for creating distributed archives of medical images in the oncology service within the framework of the federal project. The paper considers the results of the implementation of software products “LINS LookInside”, “LINS Makhaon” in the framework of implementation of local and regional projects in cancer clinics. The data on the connected diagnostic equipment and integration with medical information systems are provided. It has been established that each medical organization with an oncological profile should have its own local PACS installed. Using the example of federal cancer centers, it is recommended to include endoscopic departments, radionuclide and ultrasound diagnostics rooms in radiological information systems, as well as to install and connect systems for automatic publication of CD/DVD discs with DICOM studies.

Probing attack of share‐serial threshold implementation of advanced encryption standard

The authors present the first security evaluation of the side-channel attack countermeasure called the share-serial threshold implementation proposed by Wegener and Moradi. In the share-serial threshold implementation, all the component functions are processed using a unified circuit thereby reducing total circuit area. They show that the share-serial threshold implementation is vulnerable to probing attack using a single probe. In the proposed attack, an attacker places a single probe on a wire in the unified circuit and read the target wire over multiple cycles. The attacker can recover unshared 1-bit intermediate value by combining the measured data. The attack highlights an interesting difference between side-channel analysis and probing attack. The authors also evaluate the number of cipher calls to attack the block cipher advanced encryption standard (AES).

Modular Compact Modeling of MTJ Devices

This paper describes a robust, modular, and physics- based circuit framework to model conventional and emerging Magnetic Tunnel Junction (MTJ) devices. Magnetization dynamics are described by the stochastic Landau-Lifshitz-Gilbert (sLLG) equation whose results are rigorously benchmarked with a Fokker-Planck Equation (FPE) description of magnet dynamics. We then show how sLLG is coupled to transport equations of MTJ-based devices in a unified circuit platform. Step by step, we illustrate how the physics-based MTJ model can be extended to include different spintronics phenomena, including spin-transfer-torque (STT), voltage-control of magnetic anisotropy (VCMA) and spin-orbit torque (SOT) phenomena by experimentally benchmarked examples. To demonstrate how our approach can be used in the exploration of novel MTJ-based devices, we also present a recently proposed MEMS resonator- driven spin-torque nano oscillator (STNO) that can reduce the phase noise of STNOs. We briefly elaborate on the use of our framework beyond conventional devices.

A Family of Seismometers with Capacitive Transducers

A family of seismometers has been developed with capacitive transducers that convert the relative displacement between the inertial mass and the base of the instrument into an electric signal. These high-sensitivity seismometers have a unified electronic circuit; they can be rather easily manufactured, installed, and calibrated, which makes mass production of these instruments look promising. To assess the possibility of using these seismometers as substitutes for imported counterparts, a comparative analysis was carried out to study the performance of a portable short-period SM-3E broadband digital seismometer and imported seismometers of the same type. Seismic recordings of these instruments were statistically analyzed in the time and frequency domains.

A unified circuit for social behavior.

Recent advances in circuit manipulation technologies have enabled the association of distinct neural circuits with complex social behaviors. The brain areas identified through historical anatomical characterizations as mediators of sexual and parental behaviors can now be functionally linked to adult social behaviors within a unified circuit. In vivo electrophysiology, optogenetics and chemogenetics have been used to follow the processing of social sensory stimuli from perception by the olfactory system to valence detection by the amygdala and mesolimbic dopamine system to integration by the cerebral and cerebellar cortices under modulation of hypothalamic neuropeptides. Further, these techniques have been able to identify the distinct functional changes induced by social as opposed to non-social stimuli. Together this evidence suggests that there is a distinct, functionally coupled circuit that is selectively activated by social stimuli. A unified social circuit provides a new framework against which synaptopathic autism related mutations can be considered and novel pharmacotherapeutic strategies can be developed.

Dynamic Wireless Charging for Inspection Robots Based on Decentralized Energy Pickup Structure

To deal with the problems of charging for inspection robots in substations such as frequent charging, complex mechanical interface, and insufficient battery capacity, a dynamic wireless charging system is proposed. The structure design of energy pickup device and the indispensable positioning strategy is presented in this paper. First, the dynamic wireless charging systems based on centralized energy pickup and decentralized energy pickup (DEP) are investigated and the unified circuit model is built for two kinds of systems simultaneously. Based on the comparison of working performances, the DEP structure is selected as the pickup device in this paper. Then, the positioning scheme is realized based on imitative relaying coil structure including the DEP device and the additional sensor coil. A switching control strategy of the segmented transmitting coils is proposed further to implement the dynamic wireless charging for inspection robots. The theoretical analyses are validated by the relevant experiments.

3D Grid Multi-Wing Chaotic Attractors

As reported in the existing literature, wing attractors are confined to 1D [Formula: see text]-wing attractors, 2D [Formula: see text]-grid wing attractors. In this paper, we break this limitation and generate 3D [Formula: see text]-grid multi-wing chaotic attractors (GMWCAs). The 3D GMWCAs are produced via the following three steps: (1) applying rotation transformation to a double-wing Lorenz-like system to ensure that its saddle-focus equilibria with index 2 are located on the plane [Formula: see text]; (2) extending the wing attractors of the transformed Lorenz-like system along the [Formula: see text]-axis to have mirror symmetry; (3) introducing stair switching functions to increase the number of saddle-focus equilibria with index 2 along the [Formula: see text]-axis and [Formula: see text]-axis. Furthermore, some basic dynamical properties of the 3D chaotic system, including equilibria, symmetry, dissipativity, Lyapunov exponents and bifurcation diagram, are investigated and a module-based unified circuit diagram is designed. The effectiveness of this approach is confirmed by both numerical simulations and electrical circuit experiment.