Abstract: A method of inspecting district heating pipes consists in introducing into the pipe a vehicle including an uninflated balloon and a pulley in which a cable is inserted. The vehicle is immobilized in the pipe by inflating the balloon. A sensor is moved in the pipe by fixing it to one end of the cable and pulling on the other end of the cable to move the sensor toward the immobilized vehicle in order to inspect the pipe. The vehicle includes a parachute and is propelled in the pipe by introducing into the pipe a fluid under pressure that acts on the parachute. The balloon is deflated when the sensor reaches the vehicle immobilized in the pipe. The vehicle and the sensor are withdrawn from the pipe by pulling on the end of the cable so that the inspection is carried out during the return travel of the vehicle and the sensor. With this method, the inspection can be carried out with access from only one end of the pipe.

Abstract: A sensor for detecting defects in a component includes an electric coil fed with a varying electrical current to create a varying magnetic field penetrating at least partly into the component under test, and a defect detector including a magnetoresistor. The above components are accommodated in a protective housing having a detection face disposed near and parallel to a surface of the component under test. The coil has its axis &Dgr; perpendicular to the detection face and the magnetoresistor is in the vicinity of the detection face. The magnetoresistor is a giant magnetoresistor and is disposed so that its sensitivity axis &Dgr;1 sensitive to variations in a magnetic field is parallel to the detection face of the housing.

Abstract: A method of inspecting district heating pipes consists in introducing into the pipe a vehicle including an uninflated balloon and a pulley in which a cable is inserted. The vehicle is immobilized in the pipe by inflating the balloon. A sensor is moved in the pipe by fixing it to one end of the cable and pulling on the other end of the cable to move the sensor toward the immobilized vehicle in order to inspect the pipe. The vehicle includes a parachute and is propelled in the pipe by introducing into the pipe a fluid under pressure that acts on the parachute. The balloon is deflated when the sensor reaches the vehicle immobilized in the pipe. The vehicle and the sensor are withdrawn from the pipe by pulling on the end of the cable so that the inspection is carried out during the return travel of the vehicle and the sensor. With this method, the inspection can be carried out with access from only one end of the pipe.

Abstract: A sensor for detecting defects in a component includes an electric coil fed with a varying electrical current to create a varying magnetic field penetrating at least partly into the component under test, and a defect detector including a magnetoresistor. The above components are accommodated in a protective housing having a detection face disposed near and parallel to a surface of the component under test. The coil has its axis &Dgr; perpendicular to the detection face and the magnetoresistor is in the vicinity of the detection face. The magnetoresistor is a giant magnetoresistor and is disposed so that its sensitivity axis &Dgr;1 sensitive to variations in a magnetic field is parallel to the detection face of the housing.

Abstract: A device for inspecting a part by eddy currents, the device comprising at least one measurement bridge having an active coil which is connected between a first terminal and a second terminal, and a reference circuit which is connected between said second terminal and a third terminal, said first and third terminals being for connection to an AC voltage generator so that an alternating magnetic field is generated by the active coil in the part to be inspected in order to enable any variation in the impedance of the active coil on passing over a defect in a part under inspection to be detected by analyzing an output voltage of the device, wherein the reference circuit is a reference coil identical to the active coil, wherein the first terminal and the third terminal are for receiving voltages applied by the AC voltage generator which are equal in value and of opposite signs relative to a neutral phase of said generator, the output voltage being the voltage read between said second terminal and said neutral phas

Abstract: A device for displacing a member in a graduated and motor-driven manner inside a tube that is external to the device, the member being displaced from one end of the tube, the displacement being evaluated by at least one position encoder delivering information on the position of the member placed at one end of a tubular element which is mounted to move in translation on a support body for supporting the device. The tubular element is in the form of a member-carrying worm which is provided with longitudinal toothed racks on its periphery. The worm is displaced in translation relative to the body which carries it under the action of a first toothed belt which is mounted on the support body, which is driven by a motor fixed to the body, and which is meshed with one of the racks. Another of the racks meshes with a second toothed belt which entrains a position encoder fixed to the body.

Abstract: A transformer has its primary windings connected in series with the pumping motor and has secondary windings powering in cascade a rectifier and a voltage limiter regulating the voltage supplied to the auxiliary equipment by diverting excess current supplied by said secondary windings.

Abstract: A method is described for ordering a plurality of messages from a plurality of sources wherein, in order for all the application processes to receive the messages in the same order, a single relay process common to all the sources is selected from the application processes, the other application processes constituting slave processes. All messages broadcast by the sources are rebroadcast from the relay process to all the application processes, including the relay process. The relay process processes data from all messages that it rebroadcasts. The slave process processes only data from messages received via the relay process, data from messages received directly from the sources not being processed. Applications include data processing systems, in particular where part of the software is replicated.

Abstract: A method of scheduling tasks subject to timing and succession constraints essentially comprises grouping the tasks in layers according to succession constraints and scheduling the tasks layer by layer in increasing layer order up to the last layer, if possible, and then deciding that the resulting scheduling succeeds. If the scheduling achieved in a layer other than the first layer does not satisfy one or more constraints applying to a task belonging to the current layer, the method reschedules a layer containing a predecessor task corresponding to an unsatisfied constraint, schedules or reschedules all the other layers higher than the layer of the predecessor task, up to the last layer, if possible, and then decides that the resulting scheduling succeeds. Applications include scheduling of transmission of information on an industrial data bus.

Abstract: An electric machine control system includes a torque smoothing device including a torque monitoring device connected to the electric machine and supplying torque signals. A smoothing processor receives the torque signals and receives at least one torque reference signal and produces torque smoothing signals. A smoothing generator receives the smoothing signals and supplies smoothing electric power to the machine to make its torque conform to the torque reference.

Abstract: A window manager for a windowing system includes a window server to command the display on screen of first windows reserved by client programs of the system. The window manager manages the disposition and the circulation of first windows within a second window reserved by the system. The server holds in memory a tree structure of windowing data on the basis of which the window server communicates with the screen window manager and with the client programs. This structure has a root defining the second window and nodes defining corresponding first windows. The window manager manages in the root a first list of identifiers of first windows and detects in each node the presence or the absence of control data. If control data is present in a node defining a particular first window, the window manager manages the disposition and the circulation of the first windows on the basis of second window data under the control of a client program.

Abstract: The invention concerns a branch connector device for a shielded cable connecting a plurality of stations of a land network. The device comprises:a junction box (Bi) comprising a housing, an electromagnetic shield (EBi) and two entries for two respective sections (Ci, C'i) of the shielded cable;a connector (Mi) comprising a plurality of contacts and an electromagnetic shield.According to the invention the housing of the junction box forms the housing of the connector; the shield (EBi) of the junction box also forms the shield of the connector; and the conductors of each section of the cable are connected directly to the contacts of the connector. Applicable to industrial data processing.

Abstract: A method of scheduling successive tasks subject only to timing constraints calculates for each task upper and lower limits of the interval in which execution of that task must start. It then constructs a first series in which all the tasks are scheduled in increasing order of their lower limit and a second series in which all the asks are scheduled in increasing order of their upper limit, before constructing an initial permutation by scheduling all the tasks in the order of the first series and verifying if the initial permutation satisfies all the constraints. If not all the constraints are satisfied, the method determines in the initial permutation the first ill-placed task for which a constraint is not satisfied and a candidate task in the second series immediately preceding the ill-placed task in the second series in the current permutation.

Abstract: To interconnect the screens (4, 29) of all the screened cables the box includes:a conductive enclosure (15, 19) forming a Faraday cage;a metal plate (5) with holes (7) for fixing each cable (1, 22, 18) using a self-locking tie (6, 20);and lugs (25) cut out from the plate and bent out of the plane of the plate to constitute crimping or soldering connection points for interconnecting the screens of the cables and connecting them to ground, either via a filter (11) connected to the conductive enclosure (15, 18) for high-frequency currents, or directly by a grounding wire.Applications include industrial computer networks.

Abstract: A method of operating a data processing system adapted for running two or more identical-data-receiving replicated tasks in parallel, in which method messages are transferred to the replicated tasks, each message including such data and a time stamp, the messages transferred to each replicated task being sequenced in chronological order so as to be processed by the replicated task in that order, and a stability time is determined for each message, which stability time defines the instant from which the replicated task may process the message, wherein the sequencing of the messages transferred to a replicated task is based on the message time stamps plus respective first time constants, and the stability times of the messages are determined on the basis of the message stamps plus respective second time constants.

Abstract: Each node (N1) of the network is connected to each of the subscriber sets (P1-1) that are associated with the node via a single optical fiber (FP1-1) on two different wavelengths. The node is connected to each of certain other nodes via a single fiber (FN1-2) on a single wavelength. In the node, the electrical signals are supplied by two optical receivers (2, 6) and are transmitted via amplifiers (8, 10) to a single transmitter (4). A passive directional coupler (22) and a wavelength separator (20) provide the necessary optical connections. Passive optical dividers (24, 26) form two interfaces with the sets and with the other nodes. The invention is applicable in particular to industrial transmission networks.

Abstract: The invention relates to an object-oriented software system having replicated objects and which makes it possible to control a monitoring/control installation of redundant architecture and comprising at least one first processor (1) and one second processor (1'). The software system (2) comprises software objects (3) intercommunicating by means of messages via a dynamic object messaging mechanism. A replica (2') of the software system (2) is contained in the second processor (1'). Certain objects (3) of the software system (2) are marked and the dynamic object messaging mechanism (5) includes monitoring means (51) for identifying an object message addressed to a marked object, and means (52) for passing on the contents of the object message, in the form of a network message, to the second processor (1'). In response to the network message, the dynamic object messaging mechanism (5') in the second processor (1') activates the replica (3') of the marked object (3).

Abstract: A method of transmitting data between a set of data processing nodes interconnected by a communications network. Each node broadcasts data to the other nodes by causing a train of such data to travel over the network around a looped circuit or "ring" passing through each of said nodes, each node in the ring having a predecessor and a successor. A counter is provided in the data train, and on receiving a data train sent by its predecessor, each node recovers the counter from the received data train, increments the counter, and dispatches to its successor a new data train including the counter as incremented. It also stores the new data train with the incremented counter in its memory so that it is possible to implement a simple fault recovery procedure in the event of one of the nodes becoming faulty.

Abstract: A disturbance-limiting circuit for regulation equipment connected to an actuator controlling a process in which the actuator is controlled from a reference generator unit (1) via a plurality of regulator modules (3A, 3B, . . . , 3N) having their outputs connected to a common point (UP) so that the control value provided to the actuator at said point corresponds to the mean value of the respectively-provided voltages. The circuit is constituted by a voting circuit comprising modules (4A, 4B, . . . , 4N) each inserted between the output of one of the regulator modules and a corresponding respective resistor (RA, RB, . . . , RN), connected to the common point (UP).

Abstract: A data communication field network has a plurality of subscribers connected to it in parallel which have a high input impedance as compared with the characteristic impedance of the network which comprises a main bus into which are inserted first drop and insert devices to constitute secondary buses each comprising two first branches. The connecting device comprises a cable assembly comprising at least two second drop and insert devices inserted into one of the first branches. Each second drop and insert device provides a tertiary bus comprising two second branches. Each tertiary bus is adapted to connect one subscriber and the second branches of the tertiary bus are interconnected at the subscriber connection so as to ensure continuity of the field network and to maintain impedance matching throughout the network.