Abstract: A test method for a semiconductor device having a package with airtight space, which is formed between a substrate wafer on which an element is formed and a cap wafer which is provided being opposite to the substrate wafer, comprises an applying water process in which the semiconductor device is exposed to high moisture atmosphere and cooled and a leak discrimination process in which power is supplied to the element which is formed on the substrate wafer and leak of the package is discriminated by detecting a sound wave which is generated by the semiconductor device.

Abstract: A retarding magnet assembly includes magnets configured to apply a constant drag on the rotating disk of an electromechanical electricity meter. The assembly includes upper and lower keepers secured to opposing extensions of the meter frame. A spacer is secured, at a first end, to the upper keeper, and a non-magnetic flexure spring is secured to a second end of the spacer. A pair of upper magnets are secured to the flexure spring member at opposing ends. A pair of lower magnets are secured to the lower keeper at opposing ends. The meter rotating disk extends between the upper and lower magnets. The equilibrium point of the flexure spring changes, depending on strength of the upper magnets and their consequent attraction to the upper keeper. Thus, if the upper magnets becomes stronger due to a temperature change, the attraction of the upper magnets to the upper keeper increases, and the upper magnets move closer to the upper keeper.

Abstract: A cross coil type instrument includes a plurality of coils cross-arranged around a movable permanent magnet, a needle fastened to the movable permanent magnet through a shaft projecting from the movable permanent magnet and penetrating the coils, a reset-to-zero permanent magnet arranged in the vicinity of the movable permanent magnet, and a stopper so as to make contact with the needle at a reference indication position when the movable permanent magnet is driven only by the reset-to-zero permanent magnet.

Abstract: An apparatus for ferromagnetic measurements of electric quantities comprises a coil having a hollow barrel on which a winding of a conductive wire is formed. A unit which is integral with a needle is positioned in the barrel. The needle is displaced in front of a graduated dial between a zero value and a maximum value. The movable unit is formed integrally with a first metallic plate which is displaced, in the course of the measurement of an electrical quantity, relative to a second metallic plate which is fixed in the hollow barrel of the coil, as a function of the magnetic field created by the winding. At least one additional metallic plate is fixed in the hollow barrel of the coil, in such a manner as to cooperate with the movable plate to generate therewith a repulsive force in order to brake the pivoting of the pivotable unit when the electrical quantity to be measured tends to displace the needle of the movable unit beyond the maximum value of the graduation.

Abstract: A parallel conductance model of thinly laminated sand/shale sequences utilizes a sand/shale ratio, such as from a borehole televiewer or microelectric scanning tool, to derive sand layer resistivity from otherwise featureless logs of such thinly laminated formations.

Abstract: A temperature compensated magnetic damping assembly for providing a braking torque on an electroconductive disk of an induction device includes a pair of permanent magnets each having an easy axis of magnetization. Each permanent magnet provides two easy flux paths parallel to the easy axis of magnetization and separated by a dead zone. The permanent magnets are juxtaposed about a predetermined space through which the disk rotates such that the easy flux paths are perpendicular to the disk, and are aligned such that the magnetic flux passes twice through the disk in opposite directions. Flux return plates are provided adjacent to each of the permanent magnets so as to provide a flux path parallel to the disk and linking the two easy flux paths of each of the permanent magnets. In this configuration, a highly-efficient, substantially square magnetic flux loop is provided. One of the flux return plates is movable relative to the adjacent permanent magnet so as to provide series adjustment of the damping torque.

Abstract: A brake magnet for watt-hour meters using permanent magnet material of low permeability of nearly one and high coercive strength in which exact temperature compensation for a required temperature range can be achieved and which is easily manufactured. The temperature compensation elements are positioned on the surfaces of the brake magnet system away from the air gap.

Abstract: A magnetic damping system for induction devices having electroconductive disk armatures includes a low induction, high coercive force magnet that is vertically elongated and has a horizontal direction of magnetization parallel to the disk. Flux concentrating pole pieces adjoin the magnet pole faces for vertically directing two closely spaced braking magnetic fields from a pair of pole tips and into the disk. A temperature compensating arrangement covers the sides of the permanent magnet between the edges of the pole pieces to efficiently compensate for higher reversible temperature coefficients of magnet remanence.

Abstract: A magnetic brake-damper of an electric measuring instrument comprises two similarly magnetized permanent magnets with opposite poles, arranged one above the other and forming a gap accommodating part of the moving element of the instrument. Both permanent magnets are arranged so that the vector of their magnetization is parallel to the surface of the part of the moving element, accommodated in the gap.

Abstract: A watthour meter damping assembly includes a U-shaped magnetic yoke and a pair of highly coercive and anisotropic permanent magnets projecting in facing relationship from the ends of the yoke. Opposing pole faces of the magnets form an air gap receiving a meter disc to be magnetically retarded. A single temperature compensator extends over the pole faces of the permanent magnets to form a compensating shunt flux path around the air gap. The compensator and magnetic yoke extend substantially parallel to each other from the inner and outer pole faces, respectively, of the magnet pair.

Abstract: A method for the manufacture of cobalt-rare earth permanent magnets formed of consolidated particles thereof, for installation within electromagnetic devices such as induction watthour meters, and the product thereof. The method includes the magnetization of the consolidated cobalt-rare earth to substantial saturation in a predetermined polarity, the demagnetization and installation of the cobalt-rare earth permanent magnet while in a demagnetized state in an electromagnetic device, then its remagnetization in situ within the device to substantial saturation in a magnetizing field of the same predetermined polarity.

Abstract: A new and improved magnetic damping system for induction watthour meters including electromagnetically driven disk armatures. The magnetic damping system comprises cobalt-rare earth permanent magnets of relatively small mass deployed in a counterposed pair of unit assemblages each of which is positioned on an opposite side of the driven disk.