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Frequency Response Analysis (FRA) has been operated since last decade as a sensitive method in transformer internal defect recognition. This study has concentrated on influence of temperature variation of the transformer winding on FRA trace. An oil-free single phase model transformer involving concentric LV and HV windings is taken as a test object. The test object temperature is changed widely from...
The most outstanding feature of quartz crystal device is its frequency stability in wide range of temperature. In the last ten years, miniaturization of quartz devices has been accelerated. The newest resonators are 1/500 in size compared to those in ten years ago. Miniaturization of devices in general sacrifices its quality factor (Q value), S/N ratio, frequency-temperature stability, and product...
The UHF adjacent channel combiner is in a great demand because of the shortage of the frequency resource along with the development of the "China Mobile Multimedia Broadcasting (CMMB)" system and the "Digital Television Terrestrial Broadcasting (DTTB)" system. The high-selectivity band-pass filter is a must for the adjacent channel combiner. The characteristics of the frequency...
The present paper reports some computational measurements for the electrical properties of commercial Gallium Nitride blue light emitting diode (GaN blue LED). Many instruments have been used in this study to make different kinds of measurements. For example, Keithley 238 high current measure unit, Boonton 7200 capacitance meter, and wayne Kerr 6440 precision component analyzer ( within frequency...
Single step electrodeposition (ED) of CuInSe2 precursors followed by RTP annealing under sulphurising conditions constitutes a promising technology for low cost high efficiency solar cell technologies, obtaining efficiencies up to 11%. Further development of these technologies requires for a deeper understanding on the structure of the absorbers as function of the ED parameters, as well as their impact...
In the preparation of this report it has been difficult to segregate in the literature the components which fall within the scope of instrumentation and measurement. With no precedent as a guide, since the committee has not attempted in other years to divide the subject along the same lines, it has been necessary to choose the material rather arbitrarily. We have therefore looked first for new instrumentation,...
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