Power systems for modern complementary metaloxide-semiconductor (CMOS) technology are becoming harder to design. One design methodology is to identify a target impedance to be met across a broad frequency range and specify components to meet that impedance. The impedance versus frequency profiles of the power distribution system components including the voltage regulator module, bulk decoupling capacitors and high frequency ceramic capacitors are defined and reduced to simulation program with integrated circuit emphasis (SPICE) models. A sufficient number of capacitors are placed in parallel to meet the target impedance. Ceramic capacitor equivalent series resistance (ESR) and ESL are extremely important parameters in determining how many capacitors are required. SPICE models are then analyzed in the time domain to find the response to load transients.

The earliest prediction of the Sagnac effect, and of the possibility of detecting the Earth’s rotation with an interferometer of square kilometer area, is by Lodge (1893, 1897). We illustrate the extraordinary range of theoretical motivations for the experimental study of the Sagnac effect, starting with previously unpublished correspondence between Lodge and Larmor, and ending with present (and planned) ring interferometer experiments whose sensitivity to the Earth’s rotation is of the order of parts per million (billion, respectively).

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The results of a comprehensive diode study conducted using a pulsed high-current electron accelerator are reported. Time-dependent analysis of right-cylindrical graphite cathodes has shown evidence of the field emission character of the cold-cathode diode. The effects of cathode whiskers or microprojections on the diode response have been observed. Within a few nanoseconds after the voltage is applied to the diode, the whiskers explode to form cathode flares. The observed diode perveance throughout the remainder of the pulse can be explained in terms of the expansion of the plasma cathode formed by the merger of many cathode flares. Cathode plasma velocities ranged from approximately 2 to 3 cm/μsec. The observed diode behavior was consistent with that predicted by previous studies of high-voltage vacuum breakdown.

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