The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Mehdi Abbasi - One of the best experts on this subject based on the ideXlab platform.
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an sic driven modular step up converter with soft switched module having 1 1 turns ratio multiphase transformer for wind systems
IEEE Transactions on Industrial Electronics, 2019Co-Authors: Mehdi AbbasiAbstract:In this paper, a new step-up dc–dc converter module that consists of three resonant submodules interconnecting with 1:1 turns ratio three-phase transformer and coupled current-fed voltage doubler modules is presented for medium voltage dc converter design in wind energy application. By utilizing step-up resonant Circuits with three-phase transformer and combining it with a “multistring” inverter, the proposed circuit structure completely utilizes all the Switching Circuits to transfer power to the output. In addition, the proposed topology is able to achieve high voltage gain without using large turns ratio high frequency step-up transformers. Zero voltage Switching turn- on and near zero current Switching (ZCS) turn- off are maintained for all the switches. A modular 1.5 MW, 1 kV (dc-link), 20 kV (output) converter system is presented to validate the performance of the proposed circuit. Experimental results on a laboratory-scale 2.8 kW, 0.3 kV (dc-link), 6 kV (output), prototype are provided to highlight the merits of this work. Silicon Carbide (SiC) MOSFETs and SiC Schottky diodes are utilized in both designs. Results confirm that a peak efficiency of 97.6% is achieved in the prototype.
Jehoshua Bruck - One of the best experts on this subject based on the ideXlab platform.
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probabilistic Switching Circuits in dna
Proceedings of the National Academy of Sciences of the United States of America, 2018Co-Authors: Daniel Wilhelm, Jehoshua Bruck, Lulu QianAbstract:A natural feature of molecular systems is their inherent stochastic behavior. A fundamental challenge related to the programming of molecular information processing systems is to develop a circuit architecture that controls the stochastic states of individual molecular events. Here we present a systematic implementation of probabilistic Switching Circuits, using DNA strand displacement reactions. Exploiting the intrinsic stochasticity of molecular interactions, we developed a simple, unbiased DNA switch: An input signal strand binds to the switch and releases an output signal strand with probability one-half. Using this unbiased switch as a molecular building block, we designed DNA Circuits that convert an input signal to an output signal with any desired probability. Further, this probability can be switched between 2^n different values by simply varying the presence or absence of n distinct DNA molecules. We demonstrated several DNA Circuits that have multiple layers and feedback, including a circuit that converts an input strand to an output strand with eight different probabilities, controlled by the combination of three DNA molecules. These Circuits combine the advantages of digital and analog computation: They allow a small number of distinct input molecules to control a diverse signal range of output molecules, while keeping the inputs robust to noise and the outputs at precise values. Moreover, arbitrarily complex circuit behaviors can be implemented with just a single type of molecular building block.
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on the expressibility of stochastic Switching Circuits
International Symposium on Information Theory, 2009Co-Authors: Hongchao Zhou, Jehoshua BruckAbstract:Stochastic Switching Circuits are relay Circuits that consist of stochastic switches (that we call pswitches). We study the expressive power of these Circuits; in particular, we address the following basic question: given an arbitrary integer q, and a pswitch set {1/q, 2/q, …, q−1/q}, can we realize any rational probability with denominator qn (for arbitrary n) by a simple series-parallel stochastic Switching circuit? In this paper, we generalized previous results and prove that when q is a multiple of 2 or 3 the answer is positive. We also show that when q is a prime number the answer is negative. In addition, we prove that any desired probability can be approximated well by a linear in n size circuit, with error less than q−n.
T. Sugawara - One of the best experts on this subject based on the ideXlab platform.
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numerical noise analysis for nonlinear Circuits with a periodic large signal excitation including cyclostationary noise sources
IEEE Transactions on Circuits and Systems I-regular Papers, 1993Co-Authors: Makiko Okumura, Hiroshi Tanimoto, Tetsuro Itakura, T. SugawaraAbstract:A numerical small signal noise analysis method for nonlinear Circuits with a periodic large signal excitation, e.g. mixer Circuits and Switching Circuits, is proposed. For small signal input responses, these nonlinear Circuits are modeled as their linear periodic time-varying Circuits. First, a numerical calculation method for the time-varying transfer function of a linear periodic time-varying circuit is described. Next, a noise analysis method is proposed for these Circuits which contain noise sources modeled as cyclostationary random processes. Thermal noise and shot noise in the presence of periodic large signal excitation are modeled as cyclostationary random processes, each of which is modeled as a set of stationary random processes in continuous time. Aliasing components folded back to the baseband from high-frequency bands are calculated, and their powers are accumulated until their contributions become negligible. Simulated noise figures closely matched the measured values. >
Jie Chang - One of the best experts on this subject based on the ideXlab platform.
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modular design of soft Switching Circuits for two level and three level inverters
IEEE Transactions on Power Electronics, 2006Co-Authors: Jie ChangAbstract:This paper presents a negative-bus auxiliary resonant circuit (NBARC) and novel mirror symmetrical pair of resonant link modules for soft commutation of two-level and three-level inverters. The NBARC topology reduces the power device counts and requires low device power ratings. While the basic NBARC resonant circuit is conceived and analyzed for zero-voltage Switching (ZVS) of two-level inverters, the topology and modular design approach are extended to form a pinched-link resonant stage of ZVS for three-level inverters using mirror-symmetrical pair of resonant modules. The circuit is also designed as an optional module that can be attached to a standard inverter bridge and converted into a soft-switched inverter. Experimental results verify our circuit analysis and implementation.
Makiko Okumura - One of the best experts on this subject based on the ideXlab platform.
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numerical noise analysis for nonlinear Circuits with a periodic large signal excitation including cyclostationary noise sources
IEEE Transactions on Circuits and Systems I-regular Papers, 1993Co-Authors: Makiko Okumura, Hiroshi Tanimoto, Tetsuro Itakura, T. SugawaraAbstract:A numerical small signal noise analysis method for nonlinear Circuits with a periodic large signal excitation, e.g. mixer Circuits and Switching Circuits, is proposed. For small signal input responses, these nonlinear Circuits are modeled as their linear periodic time-varying Circuits. First, a numerical calculation method for the time-varying transfer function of a linear periodic time-varying circuit is described. Next, a noise analysis method is proposed for these Circuits which contain noise sources modeled as cyclostationary random processes. Thermal noise and shot noise in the presence of periodic large signal excitation are modeled as cyclostationary random processes, each of which is modeled as a set of stationary random processes in continuous time. Aliasing components folded back to the baseband from high-frequency bands are calculated, and their powers are accumulated until their contributions become negligible. Simulated noise figures closely matched the measured values. >
