Abstract: A system for storing a plurality of tangible assets, the system having an RF component associable with a tangible asset, wherein the RF component has a unique identifier and is configured to receive a carrier signal and emit a modulated carrier signal, wherein modulation of the carrier signal is based on the unique identifier. The system also has an RF detection system having a plurality of RF coils, wherein each coil is arranged to emit a carrier signal and receive the modulated carrier signal emitted by the RF component, a processor in communication with each of the plurality of RF coils, wherein the processor is configured to poll the plurality of RF coils by selectively allowing current to flow through one or more of the plurality of RF coils at a time and identify the RF component based on modulation of the carrier signal.

Abstract: A pet door unit allowing entry to and egress from a dwelling of an animal includes a pet door provided with a latch. The pet door is mounted for movement to allow passage of an animal when the latch is disabled. The pet door unit includes an animal detector for detecting an animal seeking passage past the pet door. A controller allows selection of a permitted passage condition. A disabler selectively disables the latch. Other arrangements described include systems for controlling entry and exit for different animals in different time frames, systems that detect an animal by a tag carried by the animal, systems that detect a door, systems that detect whether an animal has actually passed through the door and in which direction, and systems that record time and direction of passage, a preferred coil geometry for tag detection, and a preferred latch.

Abstract: A pet door unit allowing entry to and egress from a dwelling of an animal includes a pet door provided with a latch. The pet door is mounted for movement to allow passage of an animal when the latch is disabled. The pet door unit includes an animal detector for detecting an animal seeking passage past the pet door. A controller allows selection of a permitted passage condition. A disabler selectively disables the latch. Other arrangements described include systems for controlling entry and exit for different animals in different time frames, systems that detect an animal by a tag carried by the animal, systems that detect a door, systems that detect whether an animal has actually passed through the door and in which direction, and systems that record time and direction of passage, a preferred coil geometry for tag detection, and a preferred latch.

Abstract: A communications network comprising a hierarchy of communications systems all operating within the constraints of token ring protocols and operationally defining a single shared token ring. At least one of said systems is formed by a token ring hub as disclosed and claimed in our copending application 177,764 and is connected into a system comprising the next higher hierarchal level which may be another such token ring hub or a token ring LAN system. Each said hub has means for receiving a signal which indicates that the standard token ring protocols are satisfied with respect to the direct connection of the hub of a computer having a token ring adapter card fitted, or indicative of such a computer connected to another said hub at a lower level of the hierarchy.

Abstract: In a communications network, a portable token ring hub which serves as a computer communications network for a plurality of computers and answers to the protocol requirements of the computer adapter cards configured to a token ring topology and which also serves as an expander with respect to an installed token ring LAN. The hub comprises a plurality of input/output ports including respective sockets into each of which an adapter card of a respective computer plugs, a trunk insertion unit having an outlet port to which a wander lead and a trunk coupling device plug are connected, and an internal token ring which is normally a closed ring but into which each of the said input/output ports and the outlet port are inserted by means of relay contacts in accordance with the requirements of the token ring protocol.