Abstract: There is described a method and an apparatus which comprises a reader for reading document characteristics, circuitry permitting the formation of a message confirming the holder identity, a computer connected to said reader and message means, said computer is so designed as to be able to perform from those data obtained by the reader and said means, and possibly from other remotely-conveyed data, a mathematical processing including one or a plurality of encipherings according to a public-key cryptography method and making use therefor but of public keys, means being provided to check with said computer, by a third party, and/or remotely with another computer, the expected match between said collected data, a non-secret number independent from the document, and identification data present unscrambled on the document, which match is disclosed by the mathematical processing.

Abstract: A computer system for a zone fired furnace generates a plurality of temperature set point signals for a plurality of furnace zones. The set point signals are derived from a master controller acting on the measured temperature of fluid that is heated in the plurality of furnace zones and then combined to form a heated stream. The master signal, which is a velocity type signal, is provided to a plurality of zone control stations corresponding to the plurality of furnace zones. Each zone control station integrates the master signal, and then biases the master signal for use as a zone temperature set point. The zone control station can be used to bias the individual coils so as to balance the temperature of the coils with respect to each other, or to intentionally unbalance one or more coils, as desired, so as to improve furnace operations.

Abstract: An apparatus for detecting an accident of electric wire lines a single light emitting element, a plurality of optical sensor heads arranged respectively to the lines to be observed, for modulating a light supplied form the light emitting element through a light transmission line in response to electric variations in the line, and a single light receiving element for receiving the synthetic light. Therefore, since the light transmission line is used instead of electric wires, the apparatus has good insulation characteristics and thus the apparatus is not affected by an electromagnetic induction from the electric wire lines. Moreover, since use is made of single light emitting element and single light receiving element, high S/N ratio is realized.

Abstract: A circuit breaker having three level discriminating circuits and time-current operating circuits, respectively corresponding to an instantaneous releasing, a short time characteristic releasing and a long time characteristic releasing of disconnectable contacts.

Abstract: A semantic network machine is applied to an artificial intelligence computer for performing inferential retrieval with respect to a knowledge base. A main associative memory stores the knowledge base consisting of knowledge data arranged to form a semantic network. Each knowledge data consists of a set of an object, an attribute, and a value. A sub associative memory is connected in parallel with the main memory and stores specific knowledge data including "is-a" attributes of the knowledge data. In an inferential retrieval mode, when a question associated with a given object is input, an initial retrieval condition for retrieving, from the knowledge base, knowledge data necessary for answering the question is defined.

Abstract: An information carrier (17) has formations (20,21) which are engaged by contact elements (30,32) during insertion of the carrier into a receiving member (39) the movement of the contact elements is amplified and transmitted by levers (26,33) to respective means (25,34) for providing electrical signals representing movement of the contact elements.

Abstract: Improved accuracy in solution conductivity or resistivity measurment uses a center-sampling technique in which an AC drive is applied to a conductivity cell and the conductivity cell voltage is sampled during a predetermined time interval in the center of a half cycle drive waveform. The effects of cell capacitance, and particularly the electrode-solution capacitive, are compensated by periodically sampling during a second time interval which is different from the first interval. Based upon the difference between the sampled voltages in the first and second intervals, a correction to the measured conductivity or resistivity is made to compensate for capacitance induced errors.

Abstract: A changeover contact-making apparatus with interlocking member and module of protection protected against overcurrents is provided. In a same case, two contact-making systems and coil switches are disposed on each side of a median plane PP' in which the interlocking member is placed. In one of the case inner volumes defined by the plane PP' are placed a single protection module, a tripping mechanism and the respective connection terminals.

Abstract: A testing head for attachment between a cable connected to a source of microwave test signals and a microwave device to be tested. In the testing head an appropriate sampling of transmitted and reflected test signals is accomplished, along with mixing thereof with a local oscillator signal to generate an intermediate frequency signal, which is then returned to a network analyzer for appropriate processing.

Abstract: A system to continually monitor the integrity of control and safety thermocouples within a furnace comprising a low furnace temperature reader connected in parallel with a high furnace temperature reader to a single safety thermocouple.

Abstract: For switching high voltages, high frequencies and at high numbers of switching actuations, a gas discharge structure is provided which is composed of a series circuit of two or more individual arresters which comprise electrodes of copper and which are filled with gas which is at least partially composed of hydrogen. The gas discharge path is suitable for switching frequencies in the kHz range.

Abstract: A power meter device having a transparent part and an electronic signal transmitter to permit remote meter reading has a thermal and electromagnetic interference shield for protecting the electronic transmitter means from high temperatures and r.f. interference. The shield comprises a metal-organic laminate of black and white polyester layers bonded to respective opposite sides of an aluminum foil so a portion of the foil is exposed by the black polyester along a top edge of the laminate, so portions of the black and white polyesters extend beyond the foil and are bonded together along a bottom edge of the laminiate, to provide a slit near one strip end and an interlocking or detent flap at an opposite strip end and to provide integral ground and mounting tabs in the portion of the metal foil exposed by the black polyester.

Abstract: An apparatus and method for reading a bar code marked on a surface of an item, such as a semiconductor wafer, an improved method for marking the surface and an easily decipherable bar code system are disclosed. The apparatus comprises a collimated light source, a beamsplitter, a first lens system, a second lens system, an image screen and a detector. The method comprises the steps of illuminating the bar code by directing the collimated light perpendicular to the surface, magnifying the coaxial reflected beam, projecting the reflected beam on the image screen and reading the projected image with the detector. The improved method for making the bar code marks on the surface comprises the steps of rotating a diamond impregnated nickel blade, decreasing the relative distance between the surface and the blade until the blade contacts the surface, increasing the relative distance between the surface and the blade, and repeating this process until the desired number of bars are obtained.

Abstract: A controller, for controlling an electrode boiler steam humidifier includes a plurality of current loop transformers, coupled to the boiler electrodes, for sensing the current drawn by the electrode boiler. A current level detector provides a control voltage to a solenoid controlled valve, associated with the boiler, to drain a predetermined quantity of water from the boiler and thereby reduce the electrode current, when the electrode current exceeds a predetermined upper current limit. A resettable counter is provided for limiting the number of automatic attempts which can be made to reduce the electrode current. Normal periodic actuation of the humidistat resets the counter to avoid reaching the predetermined count through long-term acquisition of isolated over-current occurrences.

Abstract: Electronic trip units employed within static trip circuit breakers are individually calibrated and automatically adjusted to ensure that the trip transfer characteristics are within specification requirements. A trimming network within the trip unit circuit contains a plurality of parallel resistors each separately connected within the circuit by means of a fusible link. Test input and output values are compard to idealized values that are binary-weighted within a look-up table in the test equipment computer. The percent correction required is determined and the appropriate links are interrupted to provide ideal trip response.

Abstract: In order visually to indicate the existence of a "continuation" current through a lightning arrester, an indicator is associated therewith, which is formed by an elastically deformable strip maintained retracted against capsule electrode by a retention mechanism which is associated with an electrical filter which causes fusion of a fusible wire under the effect of a "continuation" current. Once its end is released, the strip projects outwardly of the lightning arrester and marks the location of the defective insulation.

Abstract: In an output driver semiconductor circuit, a protection circuit is used to protect the output NPN transistor from being destroyed. The protection circuit comprises an excessive current detector for detecting an excessive collector current of the output NPN transistor, an excessive temperature detector for detecting an excessive temperature of the output transistor, and an OR gate for taking a logical sum of output signals of the detectors. According to the output signal of the OR gate, a base current of the control NPN transistor is controlled, so that a base current of the output transistor is kept below a predetermined value.

Abstract: An electric shock protector apparatus includes a circuit for detecting an electric shock current signal which has a frequency substantially higher than the line frequency of a power distribution system. The current of the power system is passed through a filter which eliminates the power supply frequency and produces a signal indicative of an electric shock current. The electric shock current signal is passed to positive and negative half-cycle operation signal circuits which transmit signals to a logic gate for operating a relay to disconnect the power source from the line conductors.

Abstract: An air gap switch assembly with a status indicator that prominently indicates when the switch is in the OFF position and disappears from view when the switch is in the ON position. The status indicator is located on the control lever for the switch, which is formed of a clear material and is difficult to see. The control lever is moveable relative to the housing of the assembly so that when the control lever is in the ON position, the portion of the lever on which the status indicator is located is hidden from view by the housing of the assembly. When the control lever is moved to the OFF position, the portion of the lever on which the status indicator is located is exposed, thereby providing an indication that the switch is in the OFF position. The switch is formed of two contacts which are biased together in electrical contact by an elongated flat metal strip. The control lever is coupled to a cam.

Abstract: An apparatus for controlling the moisture content of sand as it is transported from storage to a mold making apparatus. A conveyor is used to transport a substantially uniform layer of sand at a known rate. The electrical resistance across the sand layer is measured using a series of electrically conductive members that extend into the sand. A thermocouple or other contact device is used to obtain an average temperature of the sand layer. The electrical resistance and average temperature measurements are used in a signal processor to calculate a starting moisture content for the sand. The signal processing unit also calculates an amount of water that should be added to the sand to achieve a computed moisture content value. The signal processing unit further controls the means for adding the water to the sand so that the computed moisture content value is obtained.