2,468 research outputs found
Calculation of d- and q-axis inductances of PM brushless ac machines accounting for Skew
A hybrid two-dimensional (2-D) finite-element/analytical technique is described for predicting the d-axis and q-axis inductances of permanent magnet (PM) brushless ac machines, with due account for the influence of skew. Predicted inductances are compared with measured values for two machines having identical stators, which are skewed by one slot-pitch, but which have different rotor topologies, one having surface-mounted magnets and the other having interior magnets
Online optimal flux-weakening control of permanent-magnet brushless AC drives
An enhanced online optimal control strategy, which maximizes the flux-weakening performance of a brushless AC motor, is described, and applied to motors having different rotor topologies: interior (radial or circumferential), inset, and surface-mounted magnet. It enables the maximum inherent power capability of a brushless AC motor to be achieved independent of any variation in its parameters, and facilitates maximum efficiency over the entire speed range. It also results in good transient dynamic performance, since it is coupled with feedforward vector control based on optimal current profiles
Quasinormal modes and hidden conformal symmetry in the Reissner-Nordstrom black hole
It is shown that the scalar wave equation in the near-horizon limit respects
a hidden SL(2,R) invariance in the Reissner-Nordstrom (RN) black hole
spacetimes. We use the SL(2,R) symmetry to determine algebraically the purely
imaginary quasinormal frequencies of the RN black hole. We confirm that these
are exactly quasinormal modes of scalar perturbation around the near-extremal
black hole.Comment: 17 pages, 1 figure, version to appear in EPJ
Comparison of radiofrequency ablation versus laparoscopic adrenalectomy for benign aldosterone-producing adenoma
Environmentally Conscious Manufacturing Through Total Cost Management
Total Cost Management (TCM) is a business paradigm for managing all company resources and the activities that consume those resources with a focus on stimulating and managing improvements. We address the theoretical approach of TCM to environmental sustainability and present a practical case of using costing approaches to evaluate the sustainability of the manufacture of a recycled product. Decision aids, the QFD matrix, B2B e-commerce, allowable costs, and market-based pricing are employed to demonstrate that companies can apply the TCM model to integrate environmental policy as an essential component of corporate strategy to achieve and maintain competitive superiority
The absence of the Kerr black hole in the Ho\v{r}ava-Lifshitz gravity
We show that the Kerr metric does not exist as a fully rotating black hole
solution to the modified Ho\v{r}ava-Lifshitz (HL) gravity with
and case. We perform it by showing that the Kerr metric does not
satisfy full equations derived from the modified HL gravity.Comment: 35 pages, no figure
Diffuse interstitial and multiple cavitary lung lesions due to Talaromyces marneffei infection in a non-HIV patient
AbstractA 57-year-old man presented with unproductive cough and dyspnea for 6 months in Fujian Province, China. His misuse of a large amount of steroids (accumulated dose equivalent to 3530Â mg prednisolone) resulted in Talaromyces marneffei infection. Chest computed tomographic scan revealed diffuse interstitial and multiple cavitary lung lesions. Treatment with amphotericin B combined with itraconazole resulted in total recovery, with marked regression of lung lesions
Signature inversion -- manifestation of drift of the rotational axis in triaxial nuclei
A possible scheme of realizing shell model calculations for heavy nuclei is
based on a deformed basis and the projection technique. Here we present a new
development for odd-odd nuclei, in which one starts with triaxially-deformed
multi-quasi-particle configurations, builds the shell-model space through exact
three-dimensional angular-momentum-projection, and diagonalizes a two-body
Hamiltonian in this space. The model enables us to study the old problem of
signature inversion from a different view. With an excellent reproduction of
the experimental data in the mass-130 region, the results tend to interpret the
phenomenon as a manifestation of dynamical drift of the rotational axis with
presence of axial asymmetry in these nuclei.Comment: 10 pages, 5 figure
Two charged strangeonium-like structures observable in the process
Via the Initial Single Pion Emission (ISPE) mechanism, we study the
invariant mass spectrum distribution of . Our calculation indicates there exist a sharp peak
structure () close to the threshold and a broad
structure () near the threshold. In addition, we
also investigate the process due to
the ISPE mechanism, where a sharp peak around the threshold
appears in the invariant mass spectrum distribution. We
suggest to carry out the search for these charged strangeonium-like structures
in future experiment, especially Belle II, Super-B and BESIII.Comment: 7 pages, 5 figures. Accepted by Eur. Phys. J.
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