Results 11 to 20 of about 141,707 (269)
Commutative–non-commutative dualities [PDF]
Canadian Journal of Physics, 2020 We show that it is in principle possible to construct dualities between commutative and non-commutative theories in a systematic way. This construction exploits a generalization of the exact renormalization group equation (ERG). We apply this to the simple case of the Landau problem and then generalize it to the free and interacting non-canonical ...
Scholtz, F.G. +2 more
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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 ...
Clerbout, M., Roos, Y., Ryl, Isabelle
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Bulletin of the Australian Mathematical Society, 1984 We give examples of finite groups of odd prime power order in which the commutators lying in the centre do not generate the intersection of the centre and the commutator subgroup.
Caranti A, SCOPPOLA, CARLO MARIA
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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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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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Making Almost Commuting Matrices Commute [PDF]
Communications in Mathematical Physics, 2009 Suppose two Hermitian matrices $A,B$ almost commute ($\Vert [A,B] \Vert \leq $). Are they close to a commuting pair of Hermitian matrices, $A',B'$, with $\Vert A-A' \Vert,\Vert B-B'\Vert \leq $? A theorem of H. Lin shows that this is uniformly true, in that for every $ >0$ there exists a $ >0$, independent of the size $N$ of the matrices ...
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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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FPGA-based implementation of the back-EMF symmetric-threshold-tracking sensorless commutation method for brushless DC-machines [PDF]
, 2013 The operation of brushless DC permanent-magnet machines requires information of the rotor position to steer the semiconductor switches of the power-supply module which is commonly referred to as Brushless Commutation. Different sensorless techniques have
Darba, Araz +3 more
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Energy-Efficient Cooperative Spectrum Sensing With Reporting Errors in Hybrid Spectrum Sharing CRNs
IEEE Access, 2018 Recently, cooperative spectrum sensing (CSS) in cognitive radio networks has been extensively researched. However, most of the studies mainly focus on maximizing the spectral efficiency while the energy consumption is generally ignored.
Cong Wang +4 more
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Proceedings of the American Mathematical Society, 1987 Let R R be a principal ideal ring and M k , n {M_{k,n}} the set of k × n k \times n matrices over R R . The following statments are proved: (a) If k ≤ n
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