Abstract: A fuel cell apparatus comprises fuel cells, hydrogen generators and a control unit. A fuel cell array comprises a plurality of membrane electrode assemblies (MEAs) each having a major planar surface; the MEAs are arranged such that a first surface of a first MEA which is not a major planar surface of the first MEA faces a second surface of a second MEA which is not a major planar surface of the second MEA. A plurality of fuel cells, for example arranged in an array, are included in a blade, which is connected externally to the control unit. The apparatus can accommodate a plurality of blades. A closed reactor for the generation of hydrogen gas from a chemical hydride comprises a reaction vessel; at least one entry port; and an outlet port for outputting hydrogen gas. A unit form of a composition comprises a chemical hydride; the unit form has a volume of at least 0.01 cm3.

Abstract: A switch which avoids imparting interference noise, limiting communications speed, and imparting losses, includes n passive couplers, each of which is provided with a number k of outlets, and with an inlet suitable for receiving one input signal; and k wavelength multiplexers, each of which is provided with n inlets set to respective ones of n wavelengths. For each multiplexer, that one of its inlets which is set to one of the wavelengths, is coupled via an amplifying optical gate to one of the outlets of that one of the couplers that is organized to receive an input signal carried by the same wavelength. The switch is used in performing routing functions in communications networks having optical links.

Abstract: To simplify the connection protocols of an optical communication network using wavelength division multiplexing and to increase the throughput of the network, each node sends messages on a specific wavelength and associates destination labels with them. A network controller receives the messages and the labels and forwards the messages on the receive wavelength of their destination node(s). Applications include local area networks.

Abstract: A photonic switching network includes input ports and output ports; a modulation device associated with the input ports modulates cells addressed to the same output port onto an optical carrier having a wavelength assigned to that output port. Q optical paths offer respective time-delays of 0, 1, . . . , Q-1 cell times between the input ports and the output ports so that, on being routed from an input port to an output port, cells are switched to one of the paths with time-delay so as to reach the same output port one by one. It further includes a plurality of additional output ports each connected to a controllable time-delay element the output of which can be coupled to a recirculation input port.

Abstract: To simplify the connection protocols of an optical communication network using wavelength division multiplexing and to increase the throughput of the network, each node sends messages on a specific wavelength and associates destination labels with them. A network controller receives the messages and the labels and forwards the messages on the receive wavelength of their destination node(s). Applications include local area networks.

Abstract: A high capacity data communication network based on a parallel architecture, linking the nodes of the network itself, having a plurality of logic communication media, wherein for each communication medium a different node of the network is primarily either advantaged or at a disadvantage. As a result, the fairness of the traffic handling is assured independently of the type of protocol used.

Abstract: The apparatus includes a delay member applying delays to signals received in an optical form, which form is that of an optical-type carrier wave carrying the signals. The delays are controlled so that the signals are synchronized on reference instants. According to the invention, the delay member receives said carrier wave and applies said controlled delays thereto so as to delay the signals, while leaving them in their optical form.

Abstract: To enable a data packet to be broadcast from one input (I1) to a plurality of outputs (01, 02, 03, 06) the switching network comprises in each switching plane at least one stage (S2) comprising switches (SE4, SE5, SE6) adapted at least: to route multiple copies of a packet that has been multiplied on its upstream side (SE1), and to multiply a packet by forwarding it several times in succession to the same output; the copies thus created being routed subsequently by the switches (SE7, SE8, SE9) of a downstream stage (S3). The switching network has application to photonic ATM switching centers.