Abstract: A method of authenticating a user by capturing an image of the user, assigning a user-name, selecting an image category, selecting a pattern, selecting locations on the user's face, assigning a rotation-value, logging onto a computer, presenting images, where some images are in the image category, selecting images that are the pattern away from the images in the image category, calculating a rotation angle, projecting the selected images that are rotated by the rotation angle onto the user's face at the locations, capturing an image of the user's face with the rotated images projected thereon, and authenticating the user if the user's facial features match the user's face and the projected images are the pattern away from the images in the image-category, are at the locations, are rotated by the rotation angle, and exhibit distortion consistent with the contour of the user's face.

Abstract: A device for altering the coupling of the strings of a hollow-bodied stringed musical instrument includes a rigid member mounted within the instrument body and a mode changing mechanism for selectively connecting the bridge of the instrument with the rigid member or with the instrument soundboard. When connected with the rigid member, the bridge transfers acoustic energy from the instrument strings thereto to produce a solid body sound. When the bridge is connected with the soundboard, acoustic energy from the strings produces a hollow body sound.