Abstract: Apparatus for helping predict the occurrence of an earthquake or a volcanic eruption by detecting and recording the direction of a neutron flow generated in the earth's magma and the intensity of the neutron activity.

Abstract: This invention provides method and apparatus to predict accurately volcanic eruptions or the occurrence of earthquakes without the use of a seismometer or an incline level meter. The apparatus includes a neutron sensor, a counter and a displaying device to indicate an integrated count number or changes in count number of neutrons radiated from the earth's magma with the prediction being performed on basis of the changing count or integrated count number for a given period of time.

Abstract: A potentiometer used with a voltmeter has an impedance transformer to which a voltage to be measured is applied, a bank of resistors acting collectively as a variable resistor and having switches connected in parallel across the respective resistors of the bank, a switch control circuit, and a multiplier-setting circuit, all connected in series. The resistors have resistances r, 2r, 4r, 8r, . . . , 2.sup.n-1 r or 10.sup.0 (r, 2r, 4r, 8r), 10.sup.1 (r, 2r, 4r, 8r), . . . , 10.sup.n-1 (r, 2r, 4r, 8r), where r is a minimum, or unit, resistance value. The unit resistance value r multiplied by a multiplier N of two or more digits is equal to the resistance value of the variable resistor bank.

Abstract: The location of an aperture surrounded by a region of different brightness on a plane surface is achieved by line scanning the surface with an optical scanner while shifting the line position stepwise in an orthogonal direction. A change in brightness as the scanner passes between the region and aperture creates in the scanning signals, a pulse indication of the aperture position. Signals for a progressively changing group of successive scanning lines large enough in number to span a given aperture on either side in the orthogonal direction and include a signal for at least one line intersecting the aperture; i.e., three or more consecutive lines, are synchronously compared by time delaying the earlier signals to coincide with the real time signal. The coincidence of one or more line signals indicative of an aperture directly preceded and followed by a line signal free of an aperture indication signifies the presence of an aperture.

Abstract: A multiple function type D/A converter utilizing a ladder type resistance circuit, and capable of other mathematical functions in addition to the D/A conversion, having a series resistance circuit consisting of N number of resistors R2.sub.1 .about.R2.sub.n each having a resistance value R connected in series between an output terminal V.sub.o and one side of a terminal resistor R.sub.o which has a resistance value 2R and is connected on its other side to ground, such series circuit including a resistor connecting point between each adjacent pair of resistors R.sub.0, R2.sub.1 .about.R2.sub.N, and branching in parallel therefrom N+1 number of groups of parallel resistors 01.about.0n, 11.about.1n, . . . N1.about.

Abstract: A range switching device for an electric meter, e.g.