Abstract: An apparatus includes a valve coupled to a pressure-containing component of a wellhead assembly. The pressure-containing component can include a hollow body, a bore within the hollow body, and an access passage that is in the hollow body and is in fluid communication with the bore. The valve can include a sealing element that is positioned along the access passage and is selectively moveable between closed and open positions to control fluid flow through the access passage. During operation, the sealing element may be moved between the closed and open positions without actuating the sealing element through an outer end of the access passage. Additional systems, devices, and methods are also disclosed.

Abstract: This application discloses a hard disk drive using a self-resonant frequency band of a Voice Coil Motor far above its operational frequency band to predict Rapid Off Track events before its head stack assembly can deliver the disruption to the slider writing a track. A circuit board and/or an integrated circuit are disclosed in various embodiments to predict the ROT events using the self-resonant frequency band and/or to respond to the prediction to suppress the slider writing.

Abstract: This application discloses a hard disk drive using a self-resonant frequency band of a Voice Coil Motor far above its operational frequency band to predict Rapid Off Track events before its head stack assembly can deliver the disruption to the slider writing a track. A circuit board and/or an integrated circuit are disclosed in various embodiments to predict the ROT events using the self-resonant frequency band and/or to respond to the prediction to suppress the slider writing.