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This paper presents an on-line stabilization control method developed with the aim of maintaining transient stability in a local power system which includes large-capacity generation plants. The characteristics of this method are that the power/angle curve is estimated from the on line active and reactive power measured at the generator terminal, and the optimum generation shedding for stabilization is determined by applying the equal area method to this curve. Simulation tests using detailed models of the power system confirmed that the optimum generation shedding for stabilization could be computed for various fault conditions, both symmetrical or asymmetrical. It was also determined that the on-line data could be sampled for several tens of milliseconds after clearing the fault. Thus, this method provides effective control logic for practical stabilizing systems.  相似文献   
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Electron accumulation on the metal sides of two Schottky diodes connected metal to metal was observed as a result of the temporary variation of bias between the semiconductor sides of both diodes. The potential of the metals was found to be predictable by a theory based on a property of the Schottky diode.  相似文献   
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A high-speed carry finding device consisting of seven inhibitors, each an integrated Schottky electrode-triggered Gunn device and an m.e.s.f.e.t., was fabricated monolithically. The device could find and store carry signals of all digits in 330 ps at the worst logic case. The anode-voltage margin was 11%  相似文献   
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A Monte Carlo particle simulation of a 0.25 ?m-long gate (and 0.25 ?m-long channel) GaAs MESFET having a practical doping density and sitting on a substrate is carried out. Extremely high values of gm and Idss of 643 mS/mm and 5.35 mA/20 ?m were obtained. The near-ballistic nature of the electron transport in the FET was confirmed.  相似文献   
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During the operation of a multistage flash (MSF) evaporation plant, a rather rapid decrease was observed in the economy ratio of the plant when the dissolved oxygen (DO) content of the circulating brine was at a high level. This phenomenon was brought about by the reduction of heat transfer coefficients of condenser tubes due to sludge formation on the inside tube surface by the co-precipitation of ferric hydrous oxide with silica, alumina, and organic materials. The chemical analysis of the sludge and circulating brine showed a close relationship to DO values in the brine, the concentration of iron in the sludge, and the decreasing value of the heat transfer coefficient. The lowering of DO was found very effective for avoiding the sludge trouble.  相似文献   
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The transverse spreading velocity of a high-field domain, triggered by a pair of capacitive electrodes at the middle of a planar-type GaAs bulk element, was measured as a function of the bias electric field. The results show that the velocity increases from about 108 to 109 cm/s with an increase of the bias electric field from 2.8 to 3.15 kV/cm.  相似文献   
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Thermally stimulated current was measured to determine trap distribution and charging and discharging mechanisms in a Metal-Nitride-Oxide-Semiconductor (MNOS) diode with 16 Å oxide thickness. By changing gate voltage, heating rate and the initial flat-band voltage, the memory traps near the nitride-oxide interface were separated from the others. The general formula was derived for the thermally stimulated current in an MNOS diode and was applied to obtain the trap distribution as well as effective emission time constants. The results indicate that the memory traps are distributed 50 Å deep into the nitride film from the nitride-oxide interface. The energy level lies at around 2·55 eV from the bottom of the nitride conduction band. The charging and discharging mechanism is the cascade connection of tunneling and thermal excitation or trapping. The obtained trap distribution and the charge transfer mechanism are successful for interpreting the write-in and retention characteristics.  相似文献   
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