Abstract: A road noise-cancellation system, comprising: an actuator disposed in a vehicle cabin; a controller comprising a processor and non-volatile memory, the controller being programmed to: generate a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by the actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone; adjust the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients; store the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval; and restore the second plurality of coefficients from non-volatile memory to the noise-cancel

Abstract: A road noise-cancellation system, comprising: an actuator disposed in a vehicle cabin; a controller comprising a processor and non-volatile memory, the controller being programmed to: generate a noise-cancellation signal with a noise-cancellation filter including a first plurality of coefficients, the noise-cancellation signal being based on the first plurality of coefficients, the noise-cancellation signal being transduced by the actuator to generate a noise-cancellation audio signal based on the noise-cancellation signal, the noise-cancellation audio signal destructively interfering with an undesired noise in a noise-cancellation zone; adjust the first plurality of coefficients of the noise-cancellation filter based on one or more input signals to provide a second plurality of coefficients; store the second plurality of coefficients in the non-volatile memory during a shutdown sequence or at the end of an interval; and restore the second plurality of coefficients from non-volatile memory to the noise-cancel

Abstract: A system and method for reducing or eliminating undesirable acoustic artifacts when a vehicle is struck by road debris. The method includes generating a noise signal representative of a first acceleration detected by an accelerometer of a vehicle caused by a disturbance and generating a noise-cancellation signal via a controller within the vehicle. Residual noise resulting from the combination of the acoustic energy of the noise-cancellation signal and the disturbance is detected by a reference sensor, which generates a reference sensor signal based on the residual noise. The reference sensor signal is transmitted to an adaptive processing module to adapt filter coefficients. A second acceleration is detected by the accelerometer and a level detector calculates the absolute value of a derivative of the second acceleration. If the absolute value exceeds a threshold value, adjustment of the filter coefficients is prevented.

Abstract: Adjusting a servo control system includes identifying a gain crossover frequency for the servo control system, generating a sensitivity function for the servo control system, measuring a sensitivity peak in the sensitivity function, comparing a frequency of the sensitivity peak to the gain crossover frequency, and adjusting the servo control system in response to the comparison of the frequency of the sensitivity peak to the gain crossover frequency.

Abstract: Branched polysilane copolymers are prepared via a Wurtz-type coupling reaction by reacting a mixture of two different dihalosilanes and a single trihalosilane with an alkali metal coupling agent in an organic liquid medium. The branched polysilane copolymers are recovered from the reaction mixture. Capped branched polysilane copolymers are prepared via the same Wurtz-type coupling reaction with addition of a capping agent to the reaction mixture. The capping agent is a monohalosilane, monoalkoxysilane, dialkoxysilane, or trialkoxysilane. The branched polysilane copolymers and the capped branched polysilane copolymers are soluble in organic liquid medium.

Abstract: A method of providing a control output by selecting a controller to an actuator is discussed. A first controller having an estimator-compensator architecture is selected if the actuator is in a settle stage. A second controller having an architecture other than that of the first controller is selected when the actuator is in a track follow stage. The control output is provided from the selected controller to the actuator. The control output is indicative of the control signal.

Abstract: A method of providing a control output by selecting a controller to an actuator is discussed. A first controller having an estimator-compensator architecture is selected if the actuator is in a settle stage. A second controller having an architecture other than that of the first controller is selected when the actuator is in a track follow stage. The control output is provided from the selected controller to the actuator. The control output is indicative of the control signal.

Abstract: Adjusting a servo control system includes identifying a gain crossover frequency for the servo control system, generating a sensitivity function for the servo control system, measuring a sensitivity peak in the sensitivity function, comparing a frequency of the sensitivity peak to the gain crossover frequency, and adjusting the servo control system in response to the comparison of the frequency of the sensitivity peak to the gain crossover frequency.

Abstract: In a first method, branched polysilanes are prepared via a Wurtz-type coupling reaction by reacting a mixture of a dihalosilanes and a trihalosilanes with an alkali metal coupling agent in an organic liquid medium. The reaction mixture is free of tetrahalosilanes. The branched polysilanes are recovered from the reaction mixture. In a second method, capped-branched polysilanes are prepared via the same Wurtz-type coupling reaction noted above, with the addition of a capping agent to the reaction mixture. The capping agent can be a monohalosilane, monoalkoxysilane, or trialkoxysilane. Capped-branched polysilanes are re-covered from the reaction mixture. The branched polysilanes are soluble in organic liquid mediums.

Abstract: A disk drive includes a drive housing, one or more rotating storage disks, each having a storage surface, and a fluid diffuser. The fluid diffuser includes one or more stationary diffuser wings, each having a wing surface positioned near the storage surface. One or more of the diffuser wings can extend between two of the storage disks. The diffuser wing includes a surface deviation that disrupts the fluid flow over the wing surface that is caused by the rotating storage disk. The surface deviation can include an indentation in the wing surface or can extend from the wing surface toward the storage surface. In still another embodiment, the surface deviation includes an aperture that extends through the diffuser wing. Further, the fluid diffuser can include a plurality of surface deviations that are positioned along the wing surface. Further, a portion of the surface deviation can form an angle with the wing surface that is greater than approximately 0 degrees and less than approximately 180 degrees.