Abstract: A method for inducing a covert misclassification performed on a non-transitory computer readable medium, the method includes identifying a target position. The method further includes creating a spectral perturbation tensor. The spectral perturbation tensor is configured to shift a projection of an initial spectrum towards the target position. Additionally, the method includes combining the spectral perturbation tensor to the initial spectrum. Further, the method includes classifying the combination of the spectral perturbation tensor and the initial spectrum with an established classifier, thereby designing the spectral perturbation tensor such that the combination is misclassified.

Abstract: A viewable time piece has a face from which relative time is read. The time piece has a changeable time indicator. Symbol or image changes on the time indicator are effected by placement or replacement of at least some non-alphanumeric symbols for view that are indicative of various events over the course of a day. The time piece allows exchange and replacement of the non-alphanumeric symbols so that different events may be indicated for similar respective times over the course of a day. There may also be a system that provides time variant changes in the symbols that are displayed over the course of the day.

Abstract: A sealing unit for sealing an opening through which a rotating part passes. A rotary ring turns within a housing when a pair of flexible rings carried by the rotary ring are turned by engagement with a rotating part. The opposed faces of the rotary rings are in sliding contact with surfaces having mineral filled low friction layers. The sliding contact between the rotary ring and the surfaces having mineral filled low friction layers is established and maintain by a spring.