Abstract: An adaptive feedforward method of canceling and calibrating harmonic disturbances in a magnetic disk drive storage system includes expressing harmonic disturbances to the system as d(t) and expressing an output of the system as y(t). A control signal u(t) is used to cancel the harmonic disturbance d(t), where u(t) is the estimated value of d(t) such that u(t) is an estimated value of d(t). Estimated coefficients a.sub.i and b.sub.i of u(t) are updated using the derivatives of the estimated coefficients and a constant adaptation gain g.sub.i for the ith frequency component of the disturbance. The values of estimated coefficients are implemented in real time. The control signal u(t) is combined with the system output signal y(t) to cancel u(t) from y(t). The functions representing d(t), y(t), and u(t) are included in drive code for the system.

Abstract: The jineol extracted from scolopendra subspinipes is represented as the following formula (I): ##STR1## The jineol is obtained from scolopendra subspinipes by extracting scolopendra subspinipes with a solvent, separating an activating portion from the extracted liquid with an organic solvent, and purifying an anticancerous activating portion from the activating portion by chromatography.The jineol derivatives prepared from the jineol extracted scolopendra subspinipes are represented as the following formula (II): ##STR2## wherein each R.sub.1 and R.sub.2, independently of each other, is a hydrogen; a lower alkyl group of C.sub.1 to C.sub.6 ; a cycloalkyl group of C.sub.5 to C.sub.7 having a substituting group; an alkyl group of C.sub.1 to C.sub.4 having a phenyl group with one to three substituting groups; a lower alkyl group of C.sub.1 to C.sub.6 having a hydroxy, an alkoxy having C.sub.1 to C.sub.5, or an aryloxy; a lower acyl group of C.sub.1 to C.sub.7 having a hydroxy, an alkoxy having C.sub.1 to C.sub.