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Efficient techniques using linear programming already exist for solving the constrained power flow problem limited to the active powers only (DC-flow model). However the DC-flow approximation may not be sufficiently accurate for analyzing the security of s ...
This paper proposes an expert system approach for voltage and VAr control. A decentralized control mode is used so that each area performs its proper control using only its local information. It is obvious that the proposed approach does not suffer from th ...
Pump and probe measurements with femtosecond resolution are performed on a gain-clamped semiconductor optical amplifier, a structure that contains a lasing mode. The corresponding relaxation oscillations are observed in the temporal gain recovery of the am ...
For high power applications, multilevel topologies provide a number of advantages. In this paper, the single and three-phased multilevel converter is presented. Modulation methods and control schemes have been developed and tested on low-power prototypes. ...
Recent advances in the application of nontraditional methods and procedures for offline diagnosis and online monitoring of new and service-aged power transformers are discussed. Advanced offline methods are based on the main operational stresses (electrica ...
This paper deals with a software package for the numerical analysis in transient and steady-state modes of power electrical networks or variable speed drives with arbitrary topologies. The package is composed of a series of units, each representing a speci ...
The complex AC impedance Z of superconducting YBa2Cu 3O7 triangular networks exposed to a perpendicular magnetic field was measured with a two-coil mutual inductance technique. At temperatures close to the transition temperature, both the imaginary and the ...
A new process for infiltrating fibrous pre-forms with liquid metal is presented which eliminates the need for pressurization of the metal or pre-form chemical pretreatment. The molten matrix material and preform are held in a cermic crucible so that the me ...
With a two coil mutual inductance technique the in plane penetration depth in compact YBaCuO films was measured to be λ (0) 0.23 μm. In granular YBaCuO films the penetration depth is larger, its value is being determined by the strength of the intergranula ...
Selective single-transition cross-polarization (ST-CP) may be achieved in four-level systems such as encountered in NMR of scalar-coupled two-spin systems (for example, 15N-1H groups in peptides), by employing two selective resonant fields applied to a pai ...
