Abstract: A liquid level measuring system for a personal hydration pack using capacitive sensing pads located outside of the reservoir. Variation in the liquid level due to movement of the pack is used advantageously to increase the resolution of the measurement. An indicator shows both the liquid level and the time remaining before reservoir depletion.

Abstract: The present invention is a method and system for electronically distributing digital contents. The digital contents include textual, graphical and pictorial information. At least one portable electronic book is operative to request a digital content from a catalog of distinct digital contents, to receive and display the requested digital content in readable form. An information services system is in electrical communication with the portable electronic book to perform authentication and rendering the requested digital content. An authentication server authenticates the identity of the requesting portable electronic book. A copyright protection server renders the requested digital content sent to the requesting portable electronic book readable only by the requesting portable electronic book. At least one primary virtual bookstore is in electrical communication with the information services system. The primary virtual bookstore is a computer-based storefront accessible by the portable electronic book.

Abstract: The present invention is a method and apparatus for exchanging information between an electronic book and a cartridge. The electronic book has an on-board storage and the cartridge contains a cartridge storage. It is determined if the cartridge is present. If the cartridge is present, a transfer mode is identified. The information between the on-board storage and the cartridge storage is then transferred according to the identified transfer mode.

Abstract: A semiconductor chip integrating various functional blocks of a video codec for use in a system for real time record and playback of motion video through a computer interface such as a PC-compatible parallel port is disclosed. An innovative combination of the hardware implementing data compression and decompression based on a vector quantization algorithm with video input/output port and computer interface integrated on a single semiconductor chip provides for a cost-effective solution to processing of continuous-steam video and audio data in real time.

Abstract: In accordance with the method, first and second substantially parallel conductors are placed along a pathway and coupled to a controller in a manner so that each may carry a current independently controllable by the controller. A sensing coil is placed in a vehicle having a coil axis approximately perpendicular to the plane of the conductors so as to sense the varying magnetic field caused by varying currents through the two conductors. The controller repetitively provides a half-cycle of current of a given frequency in one of the two wires, immediately followed by another half-cycle of current of the opposite polarity or direction in the other of the two wires.