In iterative schemes of identification and control one of the particular and important choices to make is the choice for a model uncertainty structure, capturing the uncertainty concerning the estimated plant model. This is typically done in some normbounded form, in order to guarantee robust stability and/or robust performance when redesigning the controller. Structures that are used in the re...

In this article, the electrode erosion and the gap growth of spark plugs were measured on of a CNG fueled engine after durability tests. Then, the required ignition voltage and the spark quality were investigated by a spark plug test rig. Considering results of measurements, the gap growth increased as the running time increased. Thus, the gap growth of spark plugs with 200 and 280 hours runnin...

A non-stationary model of the polar gap discharge in pulsars is reviewed and modiied. It is argued that the polar gap is braking down via a number of localized spark discharges, feeding a corresponding subpulse-associated plasma columns in the pulsar magnetosphere. It is demonstrated that each spark occupies a region of the polar cap with a characteristic dimension approximately equal to the he...

We describe a simple, sturdy and reliable spark gap operating with air at atmospheric pressure and able to switch currents in excess of 10 kA with sub-nanosecond jitter. The spark gap is remotely triggered by a femtosecond laser filament. Many applications rely on the initiation of a well controlled discharge between two charged electrodes. For high current applications, a gas-filled trigger is...

This paper reports the results of a study into the effectiveness of the SPARK toolset for showing the absence of run-time errors in safety-critical Ada software. In particular, the toolset is examined to determine how effective it is in finding run-time errors in a SPARK program, and how much of the process of proving freedom from run-time errors can be performed automatically. The study identi...

J.M. Lehr, C.E. Baum, W.D. Prather and F.J. Agee High Energy Sources Division, Phillips Laboratory Kirtland AFB, New Mexico 87117 The Air Force is interested in compact ultra-wideband systems which utilize a minimum volume of high pressure gas. These desires lead us to look closely at single channel spark gaps, because both the size and volume of gas, for example, hydrogen, under pressure can b...