Abstract: A cartilage replacement or repair prosthesis comprises a layer of streamlined elastomer elements, preferably in the form of spheres, supported in a matrix material so that the radially opposed surfaces of the spheres are positioned on opposite surfaces of the layer and make contact with the opposed surfaces of the femur and tibia and the forces exerted between these bones extend through the streamlined elements. The matrix material has a substantially lower resistance to deformation than the spheres to control the position of the spheres relative to one another without significantly restraining their load-responsive deformation under forces exerted between the femur and tibia. The layer, with its elastomeric inserts, is sufficiently thin and flexible to allow it to be rolled for arthroscopic insertion into a knee joint.

Abstract: A cartilage replacement or repair prosthesis comprises a layer of streamlined elastomer elements, preferably in the form of spheres, supported in a matrix material so that the radially opposed surfaces of the spheres are positioned on opposite surfaces of the layer and make contact with the opposed surfaces of the femur and tibia and the forces exerted between these bones extend through the streamlined elements. The matrix material has a substantially lower resistance to deformation than the spheres to control the position of the spheres relative to one another without significantly restraining their load-responsive deformation under forces exerted between the femur and tibia. The layer, with its elastomeric inserts, is sufficiently thin and flexible to allow it to be rolled for arthroscopic insertion into a knee joint.

Abstract: A user input having a first mode of operation relating to the entry of a command is indicated on a display device prior to the actual execution of the command, after which a second mode of operation may be entered wherein the command is actually executed using the displayed information for confirmation purposes. In a preferred embodiment, the user input device takes the form of a hand-held remote-control unit, and the display is a television monitor. In this case, the invention is operative to determine the position of a user's finger relative to one or more keys of the keypad on the remote-control unit, and display, on the TV monitor, information relating to the user's relative position.

Abstract: A user input having a first mode of operation relating to the entry of a command is indicated on a display device prior to the actual execution of the command, afterwhich a second mode of operation may be entered wherein the command is actually executed using the displayed information for confirmation purposes. In a preferred embodiment, the user input device takes the form of a hand-held remote-control unit, and the display is a television monitor. In this case, the invention is operative to determine the position of a user's finger relative to one or more keys of the keypad on the remote-control unit, and display, on the TV monitor, information relating to the user's relative position.

Abstract: A control system for a humidifier, associated with a hot air furnace, that attains a high level of relative humidity without causing any condensation on the building interior by varying the level of operation of the humidifier as a function of the rate of heat loss from the building. Since the duty cycle of the furnace is a function of the rate of the heat loss, the system generates a digital signal related to the duty cycle and uses that signal to interrogate a digital memory storing a program of desired humidities for various duty cycles to output an instantaneous desired humidity signal which is compared with a measured humidity signal to develop an on/off control signal for the humidifier.