Abstract: A portable interface for one or more electronic smart cards (74, 76), the interface being pluggable in a card reader, and comprising a module (80) that is designed to be received in the card reader and having at one end pluggable means (16) for making electrical connection with the card reader, an endpiece (18, 46, 78) secured to the other end of the module (10, 80) and including a slot (24, 48, 50) for insertion of the smart card, a housing (82, 84) designed to receive at least a portion of the smart card and passing through at least a portion of said endpiece, said housing guide and positioning means (101, 103, 102, 104) for the smart card, and electrical connection means (86, 96) for making electrical connection with the electrical contact tabs of the smart card.

Abstract: An active filter for compensation of polluting harmonics on an electricity distribution network comprising a source of energy (19, 20), a bridge converter (21) connected between the energy source and the network, control means which control the bridge converter in order to compensate for the polluting harmonics, characterized in that the state of the energy source (19, 20) is independant of the control of the bridge converter carried out by the control means (22) and in that the control means (22) control the injection of the harmonic components independantly of the state of the energy source.

Abstract: The invention provides a fluidic oscillator which is symmetrical about a longitudinal plane of symmetry (P), the oscillator comprising means for generating an oscillating two-dimensional fluid jet, an obstacle provided in its front portion with a cavity that is swept by the oscillating jet, and a longitudinal element disposed in the empty space situated downstream from said obstacle in such a manner as to partially subdivide said space into two identical zones, and to form between them at least one communication channel for the fluid. The invention also provides a fluid flow meter including such a fluidic oscillator.

Abstract: A method of controlling a device for producing or removing heat for the purpose of regulating the inside temperature of premises to comply with at least one reference q given in advance, in which, at each time instant that is separated from the following instant by a time interval .DELTA.t, a function J(u) is minimized over a duration T0 where J(u) characterizes the behavior of the inside temperature Ti of the premises, with:J(u)=.intg..sub.t.sup.t+T0 {qe.sup.2 +ru.sup.

Abstract: A signal processing circuit, including at least two stages of frequency modulation (25,20; 28, 31, 33) and demodulation of signals applied to or generated within that circuit, characterized in that the modulating and demodulating signal for each stage is an effective square wave and in that the ratio of the frequencies (F1, F2) of the modulating signals for the first and second stages corresponds substantially to the ratio of an even integer to an odd integer, or vice versa, such that there are substantially no common frequencies or harmonics between the first and second modulating signals.

Abstract: A current measurement circuit comprising a mutual inductance transformer 3, an integration circuit 2, and a dither circuit 1 which adds a square wave to the signal from the transformer 3 before the input of the integration circuit 2 in order that the integration circuit 2 provides a signal representing the measured current perturbed by a triangular dither signal.

Abstract: A system for measuring the frequency of oscillation of the fluid in a fluid oscillator comprising detector means, a peak detector comprising a threshold device receiving a first signal from the detector means, means for storing the signal at the output of the threshold device and comparator means providing an output signal in accordance with the relative values of the first signal and the signal from the memory means.

Abstract: A device for measurement of electrical energy having current and voltage sensors 1, 2, a multiplexing circuit 8 and an analogue to digital converter 11. A microprocessor 9 controls the multiplexing circuit in order to supply the current and voltage signals alternately to the converter 11, the microprocessor 9 calculating the electrical energy at a moment in time using two values of the voltage situated around a current sample and using three samples of the current. By these means the time delay between samples of the voltage and current can be corrected.

Abstract: The invention provides a method consisting successively in producing two electromagnetic radiations of the same wavelength that is modulated as a function of time over a range of wavelengths, a "measurement" one of said radiations passing through a gas that presents selective absorption for said radiation in the range, while the other radiation constitutes a "reference" radiation. Each of said radiations is transformed into a respective "measurement" or "reference" electrical signal. The measurement signal is divided by the reference signal to obtain a first quotient electrical signal which is in turn split into two portions: a time-varying AC portion and a DC portion that does not vary with time. The AC portion is divided by said DC portion in order to obtain a second quotient electrical signal representative solely of the electromagnetic radiation absorbed by the gas.

Abstract: An electricity metering device including at least one sigma-delta converter (20) adapted to output a series of digital pulses, a digital counter means (21) for summing the output of the sigma-delta converter and a signalling means (32) to deliver an output signal (38) when the sum reaches a predetermined value, characterized in that the metering device further comprises a means (32, 33) for digitally adjusting the gain of the sigma-delta converter comprising programmable digital memory means (33) adapted to store a parameter representing the gain of the metering device, the value of the parameter being externally programmable, and a digital logic means (32) for logically combining the gain parameter with the digital sum stored in the counter means to determine the number of pulses required before the predetermined value is reached and an output pulse delivered.

Abstract: An apparatus for monitoring the state of operation of lamp (2) in a public lighting network is provided comprising a sensing unit (6) associated with each lamp (2) for measuring the voltage of and luminous flux emitted by each lamp (2). Each sensing unit (6) also calculates the efficiency of lamp using an efficiency index given by the gradient of the line which, in a Cartesian diagram in which the voltage of the lamp is the x-coordinate and the flux the y-coordinate, represents the instantaneous relationship between the parameters.

Abstract: An impeller for a fluid meter, the impeller comprising a bearing including a central recess suitable for receiving a pivot, and including at the periphery of the central recess, open-ended fluting with adjacent flutes being separated by ribs. Axial passages are distributed around the fluting, with each passage co-operating with at least one flute in such a manner as to facilitate a flow of fluid via the passage to the detriment of a flow of the fluid along the flute. The impeller is applicable to metering fluids loaded with particles in suspension.

Abstract: A modulated integrator circuit frequency modulates an input signal and has an integrator comprised of an amplifier (31) and an intregrating capacitor (35) connected across an input and an output of the amplifier. The circuit further comprises a storage capacitor (36) in addition to any switching capacitors (C) associated with the modulation of the input signal if present. The storage means (36) is connectable between the input and the output of the amplifier in parallel with the integrating capacitor. The storage capacitor stores a charge associated with the voltage of the output of the amplifier and transfer such charge to the integrating capacitor to enable reversal of the charge of the integrating capacitor in synchronism with the frequency modulation of the input signal.

Abstract: A system for analogue to digital conversion comprising a means (4) for receiving an input analogue signal, a dither generator for adding a dither signal and an analogue to digital converter (2) for converting the combined input signal and dither signal to a digital value, characterized in that the dither generator provides a dither signal of a form comprising a first periodic dither signal having superimposed and being shaped by a second signal having at least one component which varies the first periodic dither signal over at least one quantization interval of the analogue to digital converter.

Abstract: A Hall effect sensor of two-dimensional electron gas type comprising, on an insulating substrate, a quantum well structure, a carrier injection layer adjacent to the quantum well structure, of thickness less than 250 .ANG. and having an density per unit area of donors integrated over the whole thickness of the carrier injection layer less than 5.times.10.sup.12 cm.sup.-2, an insulating burial layer deposited on the carrier injection layer, having a conduction band with an energy level greater than the Fermi energy of the sensor and a thickness greater than 200 .ANG.. Applicable to the field of electricity meters and current sensors.

Abstract: A fluidic oscillator flowmeter in which a two-dimensional fluid jet oscillating transfersely relative to a plane of symmetry, P, sweeps over the bottom of a cavity, and in which the flow rate is determined by electronic means from a signal, S, corresponding to a differential pressure resulting from the difference between a pressure tapped off at a point, P.sub.3, located on the axis of intersection between the plane of symmetry, S, and the bottom of the cavity and a pressure resulting from tapping off the pressure at two points, P.sub.1 and P.sub.2, which are located symmetrically on respective sides of the plane of symmetry, S.

Abstract: A fluidic oscillator and a flowmeter comprising means (10, 14, 16) for forming a two-dimensional fluid jet and an obstacle (22) having a main cavity (26) swept by the oscillating jet, and secondary cavities (34, 36) on either side of the main cavity (26) enabling the radial extension of main vortices accompanying the oscillation of the jet to be made dependent on flow conditions. Applicable to the measurement of the velocity or flow rate of flowing fluid.

Abstract: A device which removes condensation formed on the inside surface of the window of a flowmeter. The device comprises a circular skid guided for translational movement by a slideway and provided with a gutter laid against the inside surface of the window so as to remove the condensation by capillary action. The skid is moved by rotating a link driven by a manual control knob. Used for reading water meters of the dry or extra dry type.

Abstract: The invention relates to a method and a system for transmitting messages between a control terminal and controlled terminals for use especially in home automation installations. The controlled terminals are installed on a transmission network connected to the control terminal. The messages all have the same structure and include an originator field and a destination field. To install a new terminal a data item specific thereto is entered in the terminal. The new terminal installed transmits an installation request message including the specific data item to the terminal. In response the control terminal transmits an installation message which includes all the data needed for the installed terminal to converse with the control terminal.

Abstract: An aerodynamic enclosure is placed in the flow, the enclosure including an opening enabling the enclosure to be filled with the flowing fluid, and having a thermal pulse generator mounted flush with its wall, which generator is suitable for emitting modulated thermal pulses simultaneously to the outside and to the inside of the enclosure. A first thermal sensor is located in the flow and a second thermal sensor is located in the enclosure. The sensors measure propagation times or phase shifts of the thermal waves respectively in the flow and in the non-flowing fluid, thereby making it possible to deduce the value of the fluid flow rate while compensating for any variations in the temperature, pressure, and composition of the fluid. The invention is applicable to gas metering.