Results 21 to 30 of about 1,660,253 (264)
A Negative Answer to the Prime Sequence Question [PDF]
Proceedings of the American Mathematical Society, 1979 If P is a complete intersection prime, i.e., a prime ideal generated by h t ( P
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The Performance of a Three-Phase Induction Motor under and over Unbalance Voltage
Tikrit Journal of Engineering Sciences, 2022 Voltage unbalance is an adverse global phenomenon impacting three-phase induction motor output. Three-phase source voltage may become imbalanced in a variety of respects, while a balanced system preserves stable voltage magnitude and angles in three ...
Abdulsatar H. Jassim +2 more
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‘Negative repeating doublets’ in an aftershock sequence [PDF]
Earth, Planets and Space, 2013 We observed some ‘negative repeating doublets’, with nearly opposite three-component waveforms, in the aftershock sequence of the 2008 Wenchuan earthquake. The ‘negative repeaters’ are identified by using the broadband seismic record (with frequency range from 1 to 10 Hz) of the Wenchuan station (WCH) with a near epicenter distance from 19.7 to 26.6 km.
Ma, X. J., Wu, Z. L.
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Influence of Negative Sequence Injection Strategies on Faulted Phase Selector Performance
Energies, 2022 Renewable power is expected to increase drastically in the coming years due to the energy transition. A large part of the newly installed generators will be connected to the power system through inverters and electronic converters, whose behaviour ...
María Teresa Villén +3 more
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The negative sequence impedance as fault indicator in induction motors
Revista Facultad de Ingeniería Universidad de Antioquia, 2013 An algorithm to detect inter-turn faults in induction motors based on the negative sequence impedance is presented in this paper. The implementation through a digital prototype is also explained and its results are tested using a 3 Hp induction motor ...
Fernando Villada +4 more
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Orientable and Negative Orientable Sequences
Discrete Applied MathematicsAnalogously to de Bruijn sequences, orientable sequences have application in automatic position-location applications and, until recently, studies of these sequences focused on the binary case. In recent work by Alhakim et al., a range of methods of construction were described for orientable sequences over arbitrary finite alphabets; some of these ...
Chris J. Mitchell, Peter R. Wild
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Unbalanced and Reactive Currents Compensation in Three-Phase Four-Wire Sinusoidal Power Systems
Applied Sciences, 2020 In an unbalanced linear three-phase electrical system, there are inefficient powers that increase the apparent power supplied by the network, line losses, machine malfunctions, etc.
Rafael Montoya-Mira +4 more
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IEEE AccessDirectional elements are relied on to achieve selectivity in fault detection in power systems. Although such elements have been deployed successfully for many years, there is an increased need for novel methods to deal with the unique challenges of ...
Kwasi Opoku +2 more
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Energies, 2022 The growing penetration of renewable resources such as wind and solar into the electric power grid through power electronic inverters is challenging grid protection.
Almir Ekic, Di Wu, John N. Jiang
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Ultra Logconcave Sequences and Negative Dependence
Journal of Combinatorial Theory, Series A, 1997 A conjecture by Pemantle, that the convolution of ultra-logconcave sequences is ultra-logconcave, is proved. This is equivalent to the statement, that a suitable negative dependence property is preserved under the operation of sampling uniformly without replacement from two finite exchangeable Bernoulli sequences.
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