Ca(+) sparks are vascular smooth muscle cell (VSMC) Ca(2+)-release events that are mediated by ryanodine receptors (RyR) and promote vasodilation by activating large-conductance Ca(2+)-activated potassium channels and inhibiting myogenic tone. We have previously reported that exposing rats to intermittent hypoxia (IH) to simulate sleep apnea augments myogenic tone in mesenteric arteries through...

The concept of minimum ignition energy (MIE) has traditionally formed the basis for studying ignition hazards of fuels. However, the viewpoint of ignition as a statistical phenomenon appears to be more consistent with the inherent variability in engineering test data. We have developed a very low-energy capacitive spark ignition system to produce short sparks with fixed lengths of 1 to 2 mm, an...

A survey of the development of the spark chamber from the spark counter is given. An effort has been made to clarify the early history of the device. Some unpublished recent Russian work on spark chambers is summarized. A consistent terminology for the various times relevant to spark chamber operation is suggested.

Wire electrical discharge machining (WEDM) is a method to cut conductive materials with a thin electrode that follows a programmed path. The electrode is a thin wire. Typical diameters range from .004" - .012" (.10mm - .30mm) although smaller and larger diameters are available. WEDM is a thermal machining process capable of accurately machining parts with varying hardness or complex shapes. WED...

Wire electrical discharge machining (WEDM) is a method to cut conductive materials with a thin electrode that follows a programmed path. The electrode is a thin wire. Typical diameters range from .004" - .012" (.10mm - .30mm) although smaller and larger diameters are available. WEDM is a thermal machining process capable of accurately machining parts with varying hardness or complex shapes. WED...

We propose two virtual sensors which estimate the location of the pressure peak and the air-fuel ratio from measurements of the ionization current across the spark plug gap. The location of pressure peak virtual sensor produces estimates on a cycle-by-cycle basis for each of the cylinders. These estimates are twice as good as estimates obtained from a linear model. The air-fuel ratio virtual se...

The role of components in an Electrostatic Precipitator (EP) for a spark and both the phenomenon and mechanism of a spark are elaborated and then the type of spark is classified by the condition of shortage between the discharge and collecting electrodes. The secondary voltage and current waveforms of a spark are discussed in order to address the severe effect of the secondary and primary curre...

The application of ion current signals is one of the most recent approaches in engine management systems. By applying a small constant DC voltage across the electrodes of the spark plug and measuring the current through the electrode gap, the state of gas may be measured and investigated. In this paper a computer code is developed in order to analyze the state of gas during the combustion p...

Electrochemical spark machining (ECSM) is hybrid machining process which is the controlled removal of metal by anodic dissolution as well as erosion in an electrolytic cell in which the workpiece is the anode and the tool is cathode. The experimental investigation with the developed TW-ECSM set-up has been needed to understand the behaviour of the process parameters on performance characteristi...