Minimum Number Of Components Research Articles

The characterization of (𝑛 − 1)-spheres with 𝑛 + 4 vertices having maximal Buchstaber number

Abstract We present a computationally efficient algorithm that is suitable for graphic processing unit implementation. This algorithm enables the identification of all weak pseudo-manifolds that meet specific facet conditions, drawn from a given input set. We employ this approach to enumerate toric colorable seeds. Consequently, we achieve a comprehensive characterization of ( n − 1 ) (n-1) -dimensional PL spheres with n + 4 n+4 vertices that possess a maximal Buchstaber number. A primary focus of this research is the fundamental categorization of non-singular complete toric varieties of Picard number 4. This classification serves as a valuable tool for addressing questions related to toric manifolds of Picard number 4. Notably, we have determined which of these manifolds satisfy equality within an inequality regarding the number of minimal components in their rational curve space. This addresses a question posed by Chen, Fu, and Hwang in 2014 for this specific case.

Optimization design of configurable standard-type coils based on singular value decomposition for transcranial magnetic stimulation

Objective: This study aims to introduce a configurable standard-type (CST) coil design methodology that can accommodate different stimulation needs through the overlapping of standard coil components, while ensuring the performance of CST coil approaches the existing optimal physical limit as closely as possible. Approach: The study utilizes planar, spherical, and hemispherical stream function to represent the spatial geometry of the coils. Singular value decomposition is employed to design the standard coil components while minimizing the number of coil components. Initially, this study delineates the relationship between singular vectors and coil geometry, defining a multi-objective optimization problem for the research. By contrasting the decay characteristics of singular values in the inductance and electric field matrices of the stream functions, the singular vectors of the electric field matrix are utilized as the foundation for CST coil optimization. Subsequently, the relationships between the number of singular vectors and the coil’s Pareto fronts are determined through the optimization algorithms, and the geometric patterns of the singular vectors, i.e., the standard coil components, are analyzed. Main results: By constructing the CST coil components using seven singular vectors and comparing with the Pareto front of the performance of over 50 existing coil types, the stimulation depth range of the CST coil based on the planar stream function decreased by only 7.7%; the focality performance of the CST coil based on the spherical stream function improved by 22.4%; the focality performance of the CST coil based on the hemispherical stream function decreased by only 1.6%. Significance: The construction of CST coils with a minimal number of components is explored to approximate the performance at any discrete point on the physical limit curve. This approach overcomes the limitation of one coil associating with one performance point in traditional designs, presenting a novel perspective on coil design.

Comparison of climate time series – Part 5: Multivariate annual cycles

Abstract. This paper develops a method for determining whether two vector time series originate from a common stochastic process. The stochastic process considered incorporates both serial correlations and multivariate annual cycles. Specifically, the process is modeled as a vector autoregressive model with periodic forcing, referred to as a VARX model (where X stands for exogenous variables). The hypothesis that two VARX models share the same parameters is tested using the likelihood ratio method. The resulting test can be further decomposed into a series of tests to assess whether disparities in the VARX models stem from differences in noise parameters, autoregressive parameters, or annual cycle parameters. A comprehensive procedure for compressing discrepancies between VARX models into a minimal number of components is developed based on discriminant analysis. Using this method, the realism of climate model simulations of monthly mean North Atlantic sea surface temperatures is assessed. As expected, different simulations from the same climate model cannot be distinguished stochastically. Similarly, observations from different periods cannot be distinguished. However, every climate model differs stochastically from observations. Furthermore, each climate model differs stochastically from every other model, except when they originate from the same center. In essence, each climate model possesses a distinct fingerprint that sets it apart stochastically from both observations and models developed by other research centers. The primary factor contributing to these differences is the difference in annual cycles. The difference in annual cycles is often dominated by a single component, which can be extracted and illustrated using discriminant analysis.

A single-phase direct buck-boost AC–AC converter with minimum number of components

In this paper, a single-phase direct pulse width modulation (PWM) buck-boost AC–AC converter is proposed. The proposed converter utilizes a minimum number of semiconductor switches and passive components that decreases the converter power losses and offers high efficiency. It can be operated with simple PWM control and doesn’t require soft-commutation strategies. It does not suffer from input source shoot-through and commutation problems. Moreover, it supplies both continuous input and output currents. The common sharing ground of the input and output gives the proposed converter the feature that it can be utilized for voltage sag and swell compensation. A comparison of the proposed converter performance with similar existing converters is presented. Also, detailed circuit analysis, component design guidelines, and simulation results using the MATLAB/Simulink environment are demonstrated. A laboratory prototype has been built and tested to validate the converter performance and confirm the results obtained by computer simulation.

A Non-Isolated Multiport Converter for E-Vehicle Applications

The necessity to reduce the risks in the environmental pollution has paved way for the options that help in minimizing it. Electric vehicle is one such option and the most evolving means in this field. The EV system in order to achieve a high peak requires multiple sources to be integration. So, a bidirectional buck boost DC to DC converter with four port is realized in this research for integration of many sources instead of using dedicated converter. This non isolated multi-port converter with compact size, minimum number of components and simple controlstructure enhances converter reliability and makes it more economical. This converter has the ability to accommodate energy sources with varying current and voltage characteristics. This converter has two input ports the DC supply & the Batteryas well as two output ports motor and auxiliary loads. This multi-port converter exhibits bidirectional power flow capability during the regenerative braking of an E-Vehicle. The converter employs three switches to control the flow of power. The article aims in studying the performance of the controller structure used in regulating the flow in power of energy sources and analyses its dynamic as well as the steady state characteristics. The design is validated using MATLAB Simulink tool to ensure its performance.

A Self-Driven Synchronous Rectification ZCS PWM Two-Switch Forward Converter With Minimum Number of Components

A new soft-switching dual-switch forward converter with self-driven synchronous rectifier is presented in this article. The proposed converter operates under discontinuous conduction mode; therefore, compared with the two-switch forward (TSF) converter, one diode along with one inductor is removed from the output side. The leakage inductance of the transformer is employed to transfer the power from the input side to the output side. To provide the zero-current switching (ZCS) condition for all semiconductor devices in both <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> and <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> instants, a delay time between the <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> -command signals of main switches along with a capacitor is used as auxiliary circuit, which eliminates the required additional switch for soft switching. Moreover, the auxiliary circuit in addition to provide soft-switching condition, resets the transformer core, resonantly. Compared with the TSF converter with the help of the new auxiliary circuit, two reset diodes at the input side can be removed. The proposed converter is controlled with duty cycle using the pulsewidth modulation. Also, a winding is added at the output side of transformer to drive the <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">MOSFET</small> of synchronous rectification. Thus, a ZCS TSF converter with the minimum number of components is proposed. The operating modes of the proposed converter along with the design approach and the stress analysis are completely considered. To verify the theoretical results, a prototype is implemented and the theoretical results are compared with the experimental results.

Design and Implementation of a Single-Phase Direct Buck AC-AC Converter with a Minimum Number of Components

Design and Implementation of a Single-Phase Direct Buck AC-AC Converter with a Minimum Number of Components

UTC Synchronized Signal Generation for Synchrophasors and Sampled Values Measurements

This article describes two methods and circuits for generation of a signal synchronized to the Coordinated Universal Time (UTC) time scale. The signal is used as a sampling clock for a synchrophasor and Sampled Values generation. Both methods use a PPS (Pulse Per Second) pulse as a synchronization signal. In the first method, the synchronization procedure is implemented entirely in a Field Programmable Gate Array (FPGA) device. The second method uses a microcontroller and a Temperature Compensated Voltage Controlled Crystal Oscillator (TCVCXO). The common feature of the presented methods is that they are cost effective and use a minimal number of components. This paper presents the implementation details of both methods as well as the measurement results, which show that the accuracy of the synchronized signals in both procedures makes them suitable for use in synchrophasors and sampled values measurements.

First order lowpass and highpass filter using pole model of operational amplifier

A novel first order lowpass (LP) and Highpass (HP) filter using VDTA and operational amplifier is presented. It is a new kind of filter structure as it uses pole model of OA and VDTA. The OA pole model as a design parameter has been successfully utilized for realization of filters resulting high performance filters. The proposed circuit uses minimum number of components. The filter offers electronic tunability of the pole frequency which is highly required in IC technology. The sensitivities of the circuit are low. The workability of the proposed filter is verified using PSPICE simulation.

Multiplexed Readout for an Experiment with a Large Number of Channels Using Single-Electron Sensitivity Skipper-CCDs.

This paper presents the implementation of a multiplexed analog readout electronics system that can achieve single-electron counting using Skipper-CCDs with non-destructive readout. The proposed system allows the best performance of the sensors to be maintained, with sub-electron noise-level operation, while maintaining low-bandwidth data transfer, a minimum number of analog-to-digital converters (ADC) and low disk storage requirement with zero added multiplexing time, even for the simultaneous operation of thousands of channels. These features are possible with a combination of analog charge pile-up, sample and hold circuits and analog multiplexing. The implementation also aims to use the minimum number of components in circuits to keep compatibility with high-channel-density experiments using Skipper-CCDs for low-threshold particle detection applications. Performance details and experimental results using a sensor with 16 output stages are presented along with a review of the circuit design considerations.

An advanced HBNP multi-level inverter for the performance enhancement with reduced components

ABSTRACT This article proposed an advanced three-phase multilevel inverter called the H-Bridge Neutral Point (HBNP) Inverter, with a minimum number of components. This inverter is designed to generate five-level output voltage using a single solar system in each phase, making it suitable for low-, medium-, and high-power applications like AC drives, grid integration of renewable energy sources, electric vehicles, and high voltage DC and AC transmission systems, etc. The proposed circuit configuration has reduced gate driver circuits, less capacitors, fewer input sources, modularity in structure, and better THD. Furthermore, the hybrid PWM control technique provides switching signals and ensures that all switches have equal conduction intervals. All of the switches have the same temperatures and voltage sharing, indicating a simpler thermal design and DC bus voltage balancing. The proposed and existing topologies are validated using MATLAB Simulink, and the proposed topology prototype is implemented in the laboratory.

2021 best paper award winners

Both papers proposed novel designs of critical components for photovoltaic applications. Paper 1 presents a high step-up converter with an hourglass-shaped impedance network. The design allows the use of non-electrolytic capacitors, which leads to reduced size and weight, as well as longer lifetime compared to conventional converters. Meanwhile, paper 2 presents an asymmetrical multilevel inverter capable of producing up to 15 output levels. Compared to state-of-the-art solutions, it uses a minimum number of components per level. In both papers, rigorous design and performance analyses are complemented by comparative studies against existing literature solutions and corroborated by experimental validations. I wish to thank the authors of all nominated articles, wishing them success in the future, and many congratulations to the winners of this year's award. Special thanks go to Dr. Paolo Manfredi (Politecnico di Torino, Italy), member of the Editorial board, for overseeing the nominations and the selection process. My sincere congratulations to the winners.

Inductanceless high order low frequency filters for medical applications

&lt;p&gt;In this paper, a designed circuit used for low-frequency filters is implemented and realized the filter is based on frequency-dependent negative resistance (FDNR) as an inductor simulator to substitute the traditional inductance, which is heavy and high cost due to the coil material manufacturing and size area. The simulator is based on an active operation amplifier or operation transconductance amplifier (OTA) that is easy to build in an integrated circuit with a minimum number of components. The third and higher-order Butterworth filter is simulated at low frequency for low pass filter to use in medical instruments and low-frequency applications. The designed circuit is compared with the traditional proportional integral controller enhanced (PIE) and T section ordinary filter. The results with magnitude and phase response were compared and an acceptable result is obtained. The filter can be used for general applications such as medical and other low-frequency filters needed.&lt;/p&gt;

The Compositionality of Facial Expressions.

The principle of compositionality, an important postulation in language and cognition research, posits that the meaning of a complex expression is determined by the meaning of its constituting parts and the operation performed on those parts. Here, we provide strong evidence that this principle plays a significant role also in interpreting facial expressions. In three studies in which perceivers interpreted sequences of two emotional facial expression images, we show that the composite meaning of facial expressions results from the meaning of its constituting expressions and an algebraic operation performed on those expressions. Our study offers a systematic account as to how the meaning of facial expressions (single and sequences) are being formed and perceived. In a broader context, our results raise the possibility that the principle of compositionality may apply to human communication modalities beyond spoken language, whereby a minimal number of components are expanded to a much greater number of meanings.

System cost minimisation in hybrid energy storage systems connected to microgrids: A comparative approach

Electricity is the most critical facility for humans. All traditional energy supplies are rapidly depleting. As a result, the energy resources are moved from traditional to non-conventional. In this research, mixture of two energy tools, namely wind and solar energy are used. Using a Hybrid Energy Storage System (HESS), continuous power can be provided. Electricity can be produced at a cost that is affordable. The integration of solar and wind in a hybrid system cause an increase in the system’s stability, which is the key benefit of this research. The system’s power transmission efficiency and reliability can be greatly enhanced by integrating these two intermittent sources. When one of the energy source is unavailable or inadequate to meet load demands, the other energy source will supply the power. The major contribution in this research is that, the proposed bidirectional single-inductor multiple-port (BSIMP) converter significantly lowers the component count, smaller circuit size and lower cost, allowing HESS to be integrated into DC microgrid. Minimum number of components are used for the same number of ESs in HESS in the proposed BSIMP converter. The hybridization of battery and supercapacitor (SC) for storage purpose is more cost effective, as compared to the battery energy storage system, thus improving the battery stress and hence used for large scale grid energy storage. SC’s are accepted as backup and found very useful in delivering high power, not possible with batteries. The use of SC in addition to batteries can be one solution for achieving the low life cycle economy. The Single Objective Adaptive Firefly Algorithm (SOAFA) is introduced for optimising the Proportional-Integral (PI) controller parameters. The system cost is reduced by about 32%, with the constraints on wind turbine swept area, PV area, total battery and SC capacity with the proposed optimisation algorithm.

Electronically Tunable 3D Autonomous Chaotic Oscillator Employing Single CCCFA and Its Extension to 4D

This work presents the realization of a novel electronically tuneable third-order autonomous chaotic oscillator using a current-controlled current conveyor feedback amplifier (CCCFA). The proposed circuit consists of a single CCCFA, two grounded passive capacitors, one inductor, and two diodes. The chaotic oscillator possesses smooth symmetrical sin-hyperbolic nonlinearity through two antiparallelly connected diodes. The electronically tunable intrinsic resistance at the X terminal serves as the bifurcation control parameter in the circuit and is controlled through bias current. Tuning of bias current enables the formation of different periodic and chaotic attractors. The proposed chaotic oscillator exhibits rich nonlinear dynamical behavior such as periodicity, antimonotonicity, and coexistence of attractors. Multistability is investigated through circuit-level simulation. The chaotic oscillator can easily be implemented in an integrated circuit as the configuration is simple, resistorless, and uses the minimum number of components in the count. Further, a higher dimensional (4D) chaotic oscillator is proposed as an extended circuit of the 3D chaotic oscillator and illustrated as an application in chaos encryption. Simulations are done using TSMC 180nm CMOS technology in PSpice. Experimental results are presented to verify the theoretical and simulation analyses of the proposed circuits.

Обзор и анализ топологий преобразователей систем электропитания на водородных топливных элементах для беспилотных летательных аппаратов киловаттного класса мощности

Рассмотрены топологии силовых преобразователей систем электропитания для энергетических установок беспилотных летательных аппаратов на водородных топливных элементах. Показано, что наиболее эффективным является выбор оптимального режима функционирования энергетической установки путем применения управляемого преобразователя со стабилизатором напряжения и буферным накопителем энергии. На основе проведенного обзора установлено: из всех рассмотренных топологий силовых преобразователей для электротехнического комплекса беспилотного летательного аппарата наиболее эффективной является топология Buck-преобразователя с минимальным количеством компонентов.

She-Pwm Low Cost Multi Level Inverter for Pv Based Water Pumping Applications

In this article different multi-level inverter (MLI) configuration is introduced by a decreased quantity of power elements. At the output side the MLI topology generates the seven level voltage waveform with minimum number of components. The said topology configuration requires less dc voltage and power semiconductor switches. It also reduces the voltage block on switches, which reduces the inverter topology complexity and costs. Such capabilities were discovered by contrasting the topology to traditional topologies from the above perspectives. Testing were carried out to demonstrate the efficacy of the generalized MLI topology in both simulation and hardware, and the findings are presented for better understanding.

Analog pile-up circuit technique using a single capacitor for the readout of Skipper-CCD detectors

With Skipper-CCD detectors it is possible to take multiple samples of the charge packet collected on each pixel. After averaging the samples, the noise can be extremely reduced allowing the exact counting of electrons per pixel. In this work we present an analog circuit that, with a minimum number of components, applies a double slope integration (DSI) and at the same time averages the multiple samples, producing at its output the pixel value with sub-electron noise. For this purpose, we introduce the technique of using the DSI integrator capacitor to add the skipper samples. An experimental verification using discrete components is presented, together with an analysis of its noise sources and limitations. After averaging 400 samples it was possible to reach a readout noise of 0.18 e- rms/pix, comparable to other available readout systems. Due to its simplicity and significant reduction of the sampling requirements, this circuit technique is of particular interest in particle experiments and cameras with a high density of Skipper-CCDs.

DESIGN ASPECTS OF INSTALLATION DEVICES OF THE SUPPORT RINGS

The processes of manufacturing machines and appliances show a continuous tendency to increase the degree of automation. An important role in the automation of manufacturing processes is played by the constructive technologicality of the product. It is important to use a minimum number of components, which have a construction as technological as possible in terms of automation. In this context, the use of supporting rings as fasteners is welcome. The design of the installation devices of these rings requires the knowledge of their deformation forces, information that is missing in the profile literature. The authors set their goal to develop the method for calculating the forces required to deform the supporting rings with a rectangular transverse profile and their maximum allowable deformations. The calculation relationships were obtained by formalizing the supporting ring through a bar with a fixed end and studying its deformation using Mohr's integral. The article lists some types of the supporting rings used in the construction of machines and appliances, their advantages and disadvantages, aspects of their automatic installation: deformation and installation methods, precision of joint orientation, optimal design, calculation of forces required for deformation and the maximum permissible deformation value. As a result of the research carried out, recommendations were developed regarding the calculation of some constructive parameters of the devices for installing the supporting rings.