Abstract: A sealing system and method for a metal roof having a plurality of sheet metal panels attached to a roof deck covered by a layer of insulation, such as polystyrene. The joints and seams formed at junctions of adjacent plates are sealed with a nonflammable or low combustible, char forming, non absorbent layer of material which is applied over the seams in a liquid or slurry form, which subsequently hardens to form a liquid proof seal to reduce the flow of molten polystyrene from melting of the adjacent layer of insulation, into the fire below.

Abstract: A communications satellite has several radiating elements connected respectively to the output ports of a hybrid matrix power amplifier the input ports of which are connected to respective output ports of a low level beam forming network. The low level beam forming network has input ports to which are applied individual beam signals and these are combined within the network to provide at the network output ports different component sums of the input signals. By selecting appropriate connections between the beam forming network and the hybrid matrix power amplifier on the one hand and between the hybrid matrix power amplifier and the radiating elements on the other hand, desired beam overlap and equal power amplifier loading can be achieved.

Abstract: A process for bonding a glass fiber reinforced plastic to a ferro-cement ucture to improve impact strength of the ferro-cement structure comprising the steps curing the ferro-cement mortar; acid etching the mortar on the side of the ferro-cement mortar to which the glass fiber reinforced plastic is to be bonded, rinsing the mortar, drying the mortar, applying a coat of adhesive to the mortar and attaching the glass fiber reinforced plastic to the bonded mortar surface. The adhesive may be partially cured if desired.