Results 21 to 30 of about 16,769 (309)
Semi-commutations and Partial commutations [PDF]
RAIRO - Theoretical Informatics and Applications, 2000 Summary: The aim of this paper is to show that a semi-commutation function can be expressed as the compound of a sequential transformation, a partial commutation function, and the reverse transformation. Moreover, we give a necessary and sufficient condition for the image of a regular language to be computed by the compound of two sequential functions ...
Mireille Clerbout +2 more
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IET Generation, Transmission & Distribution, 2022 Concerning the insufficient accuracy of the criterion for identifying commutation failure in HVDC transmission systems, a new detection method for commutation failure based on the variation rate of commutation inductance energy is proposed.
Jing Ma, Chen Liu, Peng Cheng
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Sensorless Speed Control of Brushed DC Motor Based at New Current Ripple Component Signal Processing
Energies, 2021 Signal processing of the brushed DC motor current was developed in this paper to obtain information about a rotor speed from a measured motor current. The brushed DC motor current contains a signal with a frequency proportional to the rotor speed.
Michal Vidlak +3 more
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Coordinated suppression commutation torque ripple for brushless DC motor with commutation time
IET Electric Power Applications, 2023 A commutation torque ripple suppression strategy for the brushless DC motor (BLDCM) with commutation time is proposed. First, a torque model considering back electromotive force (back‐EMF) variation is presented, and the cause of commutation torque ...
Zhongxin Wan +3 more
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Associativity as commutativity [PDF]
Journal of Symbolic Logic, 2006 AbstractIt is shown that coherence conditions for monoidal categories concerning associativity are analogous to coherence conditions for symmetric strictly monoidal categories, where associativity arrows are identities. Mac Lane's pentagonal coherence condition for associativity is decomposed into conditions concerning commutativity, among which we ...
Došen, Kosta, Petrć, Zoran
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IEEE Access, 2020 This paper proposes an improved PWM-OFF-PWM of the brushless DC motor under braking condition which can reduce commutation torque ripple. Compared with other brake modulation methods, PWM-OFF-PWM can restrain non-commutation torque ripple attributed to ...
Qixun Zhou +4 more
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Writing commutators of commutators as products of cubes [PDF]
Communications in Algebra, 2021 It is known that commutators of commutators can be written as products of cubes, with the current upper bound on the number of cubes being 60. We discuss how proofs extracted via coset enumeration can be used to investigate this problem, and exhibit a rewriting using only 14 cubes.
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Operators with commutative commutants.
Michigan Mathematical Journal, 1988 Given operators M and N on a Hilbert space H, suppose that M (resp. N) is the direct sum of k (resp. n) copies of an operator A having a commutative commutant. Suppose further that m and k are countable cardinalities (or, any cardinalities if H is separable) and that N is a quasi-affine transform of M (i.e., \(NX=XM\) for some injective operator X with
Radjabalipour, M., Radjavi, H.
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IEEE Access, 2018 Cognitive radio (CR) is a revolutionary paradigm to solve the spectrum scarcity problem in wireless networks. In cognitive radio networks, cooperative spectrum sensing is regarded as a promising approach method to significantly improve the performance of
Jun Wu +4 more
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Research on Vacuum Arc Commutation Characteristics of a Natural-Commutate Hybrid DC Circuit Breaker
Energies, 2020 Vacuum arc commutation is an important process in natural-commutate hybrid direct current (DC) circuit breaker (NHCB) interruption, as the duration of vacuum arc commutation will directly affect the arcing time and interrupting time of NHCB.
Dequan Wang +7 more
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