Abstract: An altitude estimating system for use in a movable device, comprising: (i) circuitry for detecting, for each frame of a plurality of time frames, a set of present features external from the movable device; (ii) circuitry for providing, from a set of present features detected in a first frame, a set of predicted features that represent a prediction of location of the set of present features for a second frame that follows in time the first frame; (iii) circuitry for creating a set of correlated features by correlating a set of the predicted features for the second frame with a set of present features detected for the second frame; and (iv) circuitry for providing an estimated altitude in response to the set of correlated features.

Abstract: A CRT compensation system (10) is disclosed which utilizes a cathode stabilizer circuit (16) to correct a cathode current I.sub.k which deviates from an ideal transfer function. The cathode stabilizer circuit (16) takes the cathode voltage V.sub.K and the cathode current I.sub.K and removes the ideal gamma transfer function from I.sub.K to produce a linear output. This linear output is then subtracted from the cathode voltage V.sub.K to produce an error voltage V.sub.err which is used to adjust the CRT drive to minimize the error in the cathode current. For example the V.sub.err the error voltage may be utilized to change the voltage level of the grid one element of the CRT (14). As a result, the CRT (14) will more closely approximate the ideal transfer function. The system (10) operates continuously and thus is able to correct for short term cathode current effects on a real time basis.

Abstract: A method provides peptides that are antigenic determinants identified by antibodies obtained using intact pathogenic agents that present a restricted set of antigens to surveillance by the immune system.