Analysis of factors affecting station capacitor bank switching transients

The problem presented here is a study using a computer program which predicts the transient response when energizing a station capacitor bank of a power system. The computer program gives the wave shape and magnitudes of switching surges obtained while energized capacitor banks at one location and showing the effect of switching a bank while adjacent banks are already energized. The over voltages are given in line-to-ground voltages on the line side of the capacitor banks as well as at lower voltage levels down to the customer 120 volts service voltages. The purposes are to obtain the optimum values of pre-insertion resistors, the effect of time differences of the pole closures of the three phases in a two-step switching of capacitor banks, and the effect of impedance between banks as an aid in determining the location of future capacitor banks in the station. The effect of distance between banks on the frequency of transients and on magnitude of maximum voltages is investigated --Abstract, page ii

Excitation of source electromagnetic waves at microwave frequencies using optical techniques

The coupling efficiencies for the excitation of surface electromagnetic waves (SEW} for both the prism and the grating techniques have been studied experimentally in the microwave frequency range. The grating experiments included studies of the SEW coupling efficiencies as functions of the frequency, the angle of incidence, the grating constant, the number of grating bars, and the position of the grating bar at which the maximum radiation field of the antenna was aimed. For the prism coupling technique, the coupling efficiency was studied as functions of the angle of incidence, the aiming point of the transmitting antenna on the prism base, and the height of the prism above the metal strip or the standard railroad rail. The coupling efficiency for the prism coupling technique was found to be about 60 percent, whereas for the grating technique, the coupling efficiency was found to be about 15 percent. The coupling efficiencies for either coupling technique were found to be different for metal overlaid with thin dielectric materials and uncoated metal surfaces --Abstract, pages 2-3

Investigation the integration of heliostat solar receiver to gas and combined cycles by energy, exergy, and economic point of views

Due to the high amount of natural gas resources in Iran, the gas cycle as one of the main important power production system is used to produce electricity. The gas cycle has some disadvantages such as power consumption of air compressors, which is a major part of gas turbine electrical production and a considerable reduction in electrical power production by increasing the environment temperature due to a reduction in air density and constant volumetric airflow through a gas cycle. To overcome these weaknesses, several methods are applied such as cooling the inlet air of the system by different methods and integration heat recovery steam generator (HRSG) with the gas cycle. In this paper, using a heliostat solar receiver (HSR) in gas and combined cycles are investigated by energy, exergy, and economic analyses in Tehran city. The heliostat solar receiver is used to heat the pressurized exhaust air from the air compressor in gas and combined cycles. The key parameter of the three mentioned analyses was calculated and compared by writing computer code in MATLAB software. Results showed the use of HSR in gas and combined cycles increase the annual average energy efficiency from 28.4% and 48.5% to 44% and 76.5%, respectively. Additionally, for exergy efficiency, these increases are from 29.2% and 49.8% to 45.2% and 78.5%, respectively. However, from an economic point of view, adding the HRSG increases the payback period (PP) and it decreases the net present value (NPV) and internal rate of return (IRR)

ON SOME INEQUALITIES FOR -MEASURABLE OPERATORS

This paper deals with the Choi’s inequality for measurable operators affiliated with a given von Neumann algebra. Some Young and Cauchy-Schwarz type inequalities for -measurable operators are also given

Affiliation Oriented Journals: Don’t Worry About Peer Review If You Have Good Affiliation

There has been a growing concern about fraud peer review articles that have been published in some journals in favor of their authors' affiliation, which have been discussed extensively by some researchers. This research paper introduces a new another challenge in academic world concerning journals’ editors who look at authors' affiliations rather than papers' contents. In this short paper, we will introduce this alarming problem and do an experimental test by submitting computer generated papers to some journals and finally present the results of our experiment. The paper is an expression of our concern about providing for maximum high ethics in and quality of publication policy of modern scientific journals

Total-dose radiation effects data for semiconductor devices (1989 supplement)

Steady state, total dose radiation test data are provided for electronic designers and other personnel using semiconductor devices in a radiation environment. The data are presented in graphic and narrative formats. Two primary radiation source types were used: Cobalt-60 gamma rays and a Dynamitron electron accelerator capable of delivering 2.5 MeV electrons at a steady rate