Abstract: A system for generating multiple simultaneous laser wavelengths, said system comprising: a pulsed slave laser comprising a non-linear electro-optic crystal optically coupled to a lasing crystal in a ring cavity configuration, said non-linear electro-optic crystal configured to adjust an optical path length of said ring cavity in response to an applied voltage potential; an energy pump configured to initiate a pulse cycle in said pulsed slave laser in response to a trigger; a cavity control circuit configured to apply said voltage potential to said non-linear electro-optic crystal to generate a cavity resonance condition associated with said adjusted optical path length, said cavity control circuit further configured to provide said trigger to said energy pump in response to a detection of said cavity resonance condition; and one or more seed lasers configured to inject a single frequency laser beam into said pulsed slave laser.

Abstract: A system of gravel modules to be used atop a room or other enclosure in which there is a threat of explosion. Each module has a rigid metal box frame, which contains a two layers of gravel. The lower gravel layer is screen gravel, and a layer of graded gravel is above the screen gravel. The box frame has a lower and an upper criss-cross pattern of bridge cable. A stack of wire mesh and other supporting material is laid over the lower bridge cable to support the screen gravel, and more wire mesh is laid over the screen gravel to support the graded gravel. The depths and grades of gravel are selected according to the type potential explosion, in terms of explosive fragment sizes and the nature of any expanding gases.

Abstract: A system of gravel modules to be used atop a room or other enclosure in which there is a threat of explosion. Each module has a rigid metal box frame, which contains a two layers of gravel. The lower gravel layer is screen gravel, and a layer of graded gravel is above the screen gravel. The box frame has a lower and an upper criss-cross pattern of bridge cable. A stack of wire mesh and other supporting material is laid over the lower bridge cable to support the screen gravel, and more wire mesh is laid over the screen gravel to support the graded gravel. The depths and grades of gravel are selected according to the type potential explosion, in terms of explosive fragment sizes and the nature of any expanding gases.