Abstract: A wireless remote control high security system permits the opening or theft-proof closing of relay actuating systems such as locks. The system comprises an assembly of remote control security keys and locks in which the key has the sole function of emission and the lock the sole function of reception in connection with the function of absolute security of opening or closing locks.

Abstract: An automobile burglary detecting circuit for use with an automobile electrical system having an electrical accessory activated by a switch. The detecting circuit also includes a signal generator for imposing an oscillating signal on the electrical system, and a signal detector which detects the signal from the system. An alternative embodiment includes a further signal generator which is responsive to the signal detector, and which imposes a second oscillating signal on the electrical system. The second oscillating signal is detected by a filter which activates an alarm.

Abstract: A concrete floor slab constructed from several basic prefabricated slabs. This slab comprises at least three basic slabs 1, 2 and 3 of polygonal shape, set together and arranged around a central point, with at least three anchoring units located at the central point each at least partially embedded in a basic slab, a central junction component located at the central point between the basic slabs and mechanical assembly methods for the central junction component linking it with the anchoring units.The invention applies to the construction of all types of load bearing floors and in particular those of wide span which rest directly on pillars without the intermediate use of joists.

Abstract: Assembly of prefabricated pre-stressed reinforced concrete elements solid with their reinforcements comprising linking means including at least one internally threaded cage, nuts in said cage, mounted on externally threaded parts directly or indirectly rigidly coupled to the reinforcements; the nuts abut against the cages by means of ball-and-socket bearings, thus making allowance for any misalignments of the elements. The reinforcements being solid with the concrete, this linking means affords for supplemental adjustment stress in particular elements only, whereby the assembly may be rendered statically indeterminate.