Abstract: The invention relates to the detection of liquid in a cavity of a structure, e.g. a sandwich-structure cell with honeycomb core and carbon fiber composite coating. The structure is subjected to a mechanical vibration, at a frequency fm in the audible range, by an excitation wave, the area being explored is subjected to an incident electromagnetic wave and the reflected electromagnetic wave is analyzed to deduce therefrom the presence or the absence of liquid in cavities. The Faraday wave induced on the surface of the liquid in the cavity comprises subharmonic frequencies of fm which modulate the reflected electromagnetic wave and make it possible to identify the presence of liquid. A detection apparatus comprises an excitation wave generation device for generating the vibration excitation wave, an electromagnetic wave generation device for generating the incident electromagnetic wave, a measuring device for detecting and measuring the reflected electromagnetic wave, and a signal processor.

Abstract: The invention relates to the detection of liquid in a cavity of a structure, e.g. a sandwich-structure cell with honeycomb core and carbon fiber composite coating. The structure is subjected to a mechanical vibration, at a frequency fm in the audible range, by an excitation wave, the area being explored is subjected to an incident electromagnetic wave and the reflected electromagnetic wave is analyzed to deduce therefrom the presence or the absence of liquid in cavities. The Faraday wave induced on the surface of the liquid in the cavity comprises subharmonic frequencies of fm which modulate the reflected electromagnetic wave and make it possible to identify the presence of liquid. A detection apparatus comprises an excitation wave generation device for generating the vibration excitation wave, an electromagnetic wave generation device for generating the incident electromagnetic wave, a measuring device for detecting and measuring the reflected electromagnetic wave, and a signal processor.

Abstract: A method of manufacturing a bituminous coated aggregate mix, said method comprising at least the following steps: (a) course aggregate are dried by heating; (b) an intermediate mix is formed by coating the course aggregate with hot bitumen; and (c) wet sand is mixed with the intermediate mix obtained in step (b).

Abstract: A method of laying hot blacktop paving material, the method comprising a spreading step during which the material is spread onto a surface for receiving it, and immediately prior to the spreading step, a step of adding water during which water plus wetting agent is mixed with the blacktop material.

Abstract: A method of manufacturing a bituminous coated aggregate mix, said method comprising at least the following steps: (a) chippings are dried by heating; (b) an intermediate mix is formed by coating the chippings with hot bitumen; and (c) wet sand is mixed with the intermediate mix obtained in step (b).

Abstract: A method of laying hot blacktop paving material, the method comprising a spreading step during which the material is spread onto a surface for receiving it, and immediately prior to the spreading step, a step of adding water during which water plus wetting agent is mixed with the blacktop material.

Abstract: A hand holdable manually dispensing mastic container is made from two sheets of transparent plastics material which are welded together at a seam around the periphery thereof. The container is formed to have a dispensing edge and a filling end which are parallel to one another. The container has a generally elongate shape which diverges from the dispensing edge to a widest dimension, and parallel to the dispensing edge, and then converges to the filling end. Thus, two trapezoidal portions are formed. The volume of the portion closest to dispensing edge is smaller than the volume of the portion closest to the filling end.

Abstract: The invention relates to a radioaltimeter type detector comprising an oscillator-transmitter (10), a modulator (20) suitable for frequency modulating the oscillator-transmitter according to a given characteristic, a mixer receiving the signal from the oscillator-transmitter and a corresponding echo signal reflected by a target, and a discriminator circuit (50, 60) connected to the output from the mixer. According to the invention, the modulator (20) includes a digital memory (21) containing a series of values defining the frequency modulation characteristic of the oscillator-transmitter (10).

Abstract: The invention relates to a method of regenerating the modulation carrier wave of an original modulated signal (SL) which has symmetrical frequency components about the carrier. A phase discriminator (D1) which receives two image signals (SL, S11) of the original signal controls the frequency of a local oscillator (OL), the frequency spectrum of one of the image signals being inverted with respect to that of the original signal and the difference in frequencies between these two image signals being twice that between the local carrier and the carrier of the original signal. Application to the synchronous demodulation of a television signal.