Abstract: A distributed client/server computer network wherein the identity of at least one complex image, selected from a plurality of complex images stored by a client, is transmitted to a remote server. The remote server then determines, from the identity of the or each image selected, whether the client is authorised to gain access, via the server, to a particular network resource. The network is thus efficient, as the complex images themselves do not need to be transmitted from the client to the server, and secure, as no authorization information is stored by the client.

Abstract: A method of and apparatus for determination of touch location on a display screen or the like or other surface embodying a force-sensing platform or surface supporting or otherwise externally contacting the display screen monitor apparatus, and responding to the forces created by the thrust of touching a point of the display screen, to sense and calculate the location of the touching point. The underlying technique employs force-sensing means responsive to all six degrees of freedom of applied (touching) force and torque, achieving force location away from the plane of the sensors and in spite of tangential force components by calculating the point of least magnitude of the three-dimensional torque vector from among all points within the screen or surface, and outputting this point as an estimate of the intersection point of the screen or surface with the thrust line of the touching or other contact force.

Abstract: An interactive video-audio-computer open architecture system and method with dynamically reconfigurable software providing a virtual device interface buffering applications from hardware and with extended flexibility and universal compatibility with the myriad of industry hardware products and standards (videodisc players, graphics, microprocessors, computers, video and audio sources, etc.), all with transparency to the user and without the requirement of modification of application software irrespective of which hardware product is connected to the system.

Abstract: A novel separate synchronizing error signal integrating filter section and error signal phase lock loop section independently controllable for such purposes as controlling the horizontal synchronization of overlayed video and graphic display rasters, particularly during periods of aberrant operation.