Results 221 to 230 of about 336,864 (267)

Loss phenomena in the AC quantum Hall effect

IEEE Transactions on Instrumentation and Measurement, 2001
We investigated the ac quantum Hall effect of several GaAs-based samples. The influence of temperature, current, and frequency was measured for the plateaux i=2. Some measurements of the plateaux i=4 were performed to determine the scaling behavior with respect to i.
Jürgen Schurr, Jürgen Melcher, Aurel von Campenhausen, Klaus Pierz, Günter Hein, Franz-Josef Ahlers   +5 more
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Ac loss minimum in type II superconductors

Physics Letters A, 1980
Abstract Theoretical predictions with respect to a minimum in the ac losses in type II superconductors are compared with experimental results on Nb-50% Ti and Nb-10% Mo. Extensions of the theory are suggested to explain the deviations.
Ciszek, M., Kozlowski, Gregory, Tekiel, P., Gijsbertse, E. A., van de Klundert, L. J.M.   +4 more
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ac-loss valley in type-II superconductors

Physical Review B, 1992
Hysteresis losses W have been calculated as a function of temperature T, bias field ${\mathit{H}}_{\mathit{b}}$, and amplitude ${\mathit{h}}_{0}$ for planar geometry in the critical-state framework with ${\mathit{j}}_{\mathit{c}}$=\ensuremath{\alpha}(T)/${\mathit{B}}^{\mathit{n}}$ for n=0, 1/2, and 1 in the range ${\mathit{H}}_{\mathit{b}}$/${\mathit{h}
, LeBlanc, , LeBlanc
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Comparison of calculated and measured losses in direct AC-AC converters

2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230), 2002
This paper is concerned with modelling, predicting and experimental measurement of semiconductor losses in direct AC-AC (matrix) converters. All of the commutation scenarios possible in a matrix converter topology using two or four step commutation are identified and studied.
M. Bland, P. Wheeler, J. Clare, L. Empringham   +3 more
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Review on AC losses in superconductors

IEEE Transactions on Magnetics, 1981
Paper presents principal results obtained during the last years in the research of AC losses in superconductors with regard to the magnet technology. Special emphasis is given on these aspects which are important in demonstrating the technical feasibility and economical advantages of AC superconducting windings. In the domain of hysteresis losses paper
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AC Losses in Hard Superconductors

1963
Fagan[1], McFee[2], and others have suggested the possibility of building transformers, transmission lines, rectifiers, rotating equipment, and other ac power equipment using superconductors. The practicability of many of these devices depends on the feasibility of producing superconductors that will carry high ac current densities at high ac magnetic ...
C. H. Jones, H. L. Schenk
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Measurement of ac losses of superconducting cable by calorimetric method and development of HTS conductor with low AC losses

IEEE Transactions on Appiled Superconductivity, 2003
To achieve compact and highly efficient HTS power transmission cables, reducing and evaluating AC losses is important. Furukawa is developing conductors with low AC losses of 1 W/m at 3000 Arms for the 66/77 kV class HTS cables as a part of the Super-ACE project.
M. Yagi, S. Tanaka, S. Mukoyama, M. Mimura, H. Kimura, S. Torii, S. Akita, A. Kikuchi   +7 more
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Magnetization And Ac Losses In Superconductors

1999
Abstract Magnetization losses in superconducting filaments and other losses in superconductive wires, composites and cables in time-varying magnetic fields are of considerable importance to magnet design. Important theoretical and experimental investigations in this domain had been performed since the understanding of hard Type II ...
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Ac Losses in Bi2212 ROSATwires Exposed to an Ac Magnetic Field

2000
We experimentally studied the ac loss properties of Bi2212 ROSATwires(Rotation-symmetric arranged tape-in-tube wire) with 19x6x3 thin filaments and pure silver matrix. Ac losses and I c -B characteristics of the twisted and non-twisted straight sample wires with a diameter of 1.95mm were measured in subcooled LN2 at 66K.
Masataka Iwakuma, Yuzo Fukuda, Kentaro Matsumura, Kazuhiro Kajikawa, Kazuo Funaki, Michiya Okada   +5 more
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AC Loss in a Composite Hyperconductor

1990
For high magnetic field operation at cryogenic temperatures near 20° K the best lightweight conductor presently available is high-purity aluminum, sometimes referred to as a hyperconductor. However, because of its high purity the material is mechanically weak, and because of its high conductivity the conductor must be fabricated as fine twisted strands
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