Abstract: A cleaning tool having a cleaning head disposed at the distal and of an elongated, extendable shaft. A handle at the proximal end contains a lever attached to a linkage. The cleaning head has an elbow joint and provides an attachment point for an upper support arm and a lower support arm movable with respect thereto. The elbow joint allows the cleaning head to be rotated with respect to the distal end of the elongated, extendable shaft. Two-sided pads may be attached to distal ends of both the upper arm and the lower arm. Each two-sided pad may have a different cleaning property on each of its two major faces. This allows up to four different cleaning surfaces to be present at the cleaning head of the cleaning tool of the present invention. A linkage is provided between the lever and the lower support arm.

Abstract: In an electro-mechanical distribution system having plural units each comprising a valve/switch and dual sensors, a computer is associated with each unit so as to process sensor information and control the valve/switch. According to the control logic, a unit is either in normal mode or fault mode. The fault mode begins with a transient waiting period and may continue on to a series of steps. A step waiting period (wherein the valve is closed) may be followed by the step testing period (wherein the valve is closed) of the same step; a step testing period may be followed by the step waiting period of the next step. Fault mode is triggered if at any time during normal mode either sensor detects a fault condition. Normal mode is triggered if at any time during fault mode both sensors concurrently detect a normal condition.

Abstract: A sub-micron dimensional standard is embodied in a grating of equal-sized lines and spaces formed in an electron-sensitive material by means of E-beam lithography. Several gratings are generated in the material at different respective doses of electrons. For each dose, a plurality of gratings are formed with different respective energy deposition contours over the interface of a line and a space. At one dose the energy deposition contour will be the same for all of the different energy deposition contour values. The grating formed with this dose is chosen as the one having a part which forms the standard. The width of a line, as well as the width of a space, in the selected grating is known in absolute terms to the same degree of accuracy as the grating's period. With such an artifact, the systematic error inherent to a measurement system can be determined. Once this error is known, it can be employed as a compensating factor to correct measurements made via the system.