Abstract: A method, performed by software executing on the processor of a portable music playback device, that automatically files tracks according to hierarchical structure of categories to organize tracks in a logical order. A user interface is utilized to change the hierarchy, view track names, and select tracks for playback or other operations. The user interface uses an overlapping hierarchy of categories. A song title can be accessed in multiple different ways by starting with different categories. A preferred embodiment of the invention uses the top-level categories “Albums”, “Artists”, “Genres” (or styles), and “Play Lists”. Within the Albums category are names of different albums of songs stored in the device. Within each album are the album tracks, or songs, associated with that album. Navigation is performed by presenting a sequence of display screens for each level of the hierarchy.

Abstract: A method, performed by software executing on the processor of a portable music playback device, that automatically files tracks according to hierarchical structure of categories to organize tracks in a logical order. A user interface is utilized to change the hierarchy, view track names, and select tracks for playback or other operations. The user interface uses an overlapping hierarchy of categories. A song title can be accessed in multiple different ways by starting with different categories. A preferred embodiment of the invention uses the top-level categories “Albums”, “Artists”, “Genres” (or styles), and “Play Lists”. Within the Albums category are names of different albums of songs stored in the device. Within each album are the album tracks, or songs, associated with that album. Navigation is performed by presenting a sequence of display screens for each level of the hierarchy.

Abstract: A method, performed by software executing on the processor of a portable music playback device, that automatically files tracks according to hierarchical structure of categories to organize tracks in a logical order. A user interface is utilized to change the hierarchy, view track names, and select tracks for playback or other operations.

Abstract: A technique for managing the modes of the hard disk drive to extend battery life and reduce noise. The technique may be implemented by a processor in a portable digital music player that stores audio tracks on a hard disk drive, for example. This technique includes reading a block of audio data from the disk and storing the block in a buffer while the disk is spinning. Subsequent to reading the block, the disk is spun down to a power-saving mode, while the block is played from the buffer. While the block is being played from the buffer, the technique includes monitoring the amount of the block left to be played. When the amount the block left to be played drops below a low threshold level, the disk is transitioned from the power saving mode back to a spinning mode so that data can be read from the disk before the block is finished being played from the buffer.

Abstract: A method, performed by software executing on the processor of a portable music playback device, that automatically files tracks according to hierarchical structure of categories to organize tracks in a logical order. A user interface is utilized to change the hierarchy, view track names, and select tracks for playback or other operations.

Abstract: A technique for extending battery life and reducing noise in a portable music player storing tracks on a hard drive reads a track from the disk to a buffer and plays the track from the buffer while the disk is spun down to a power-saving state. Noise and vibration is also reduced when the disk is spun down.

Abstract: The properties of porous material that is hydraulically coupled to a well through openings in cased or in uncased portions of the well are evaluated. The process involves initiating a pressure wave, typically at the well head, so that the pressure oscillations extend to the porous material zone under investigation. Flow of fluid between the well and formation changes the amplitude and frequency content of the oscillations traveling up and down the well. That is, the oscillations are modulated from the form they would have in a like well with no hydraulic communication to the formation. The properties of the formation are derived from these changes.

Abstract: A method of testing a water or petroleum well to obtain information about well features, especially that part of the well beneath the ground surface, is described. The method is especially useful in detecting problems or irregularities in the well such as stuck tools, casing damage, damaged zones in an uncased well, or debris in a well. The method involves creating oscillations in the fluid pressure in the well. Transducers measure the pressure oscillations. The measured pressure oscillations are used to determine resonant frequencies. The measured resonant frequencies are used to determine the characteristic impedance and the depth of each reflector in the well, after removing resonances caused by known reflectors. It is then possible to determine the nature of each unknown reflector based on suspected problems or the well's operational history.