Systems and methods for detecting corrosion in pipes are disclosed herein. In one embodiment, an apparatus for detecting corrosion in an object includes an electromagnetic acoustic transducer (EMAT) having a ferromagnetic core and a plurality of permanent magnets arranged peripherally around the ferromagnetic core. The permanent magnets are arranged to produce a magnetic field through the ferromagnetic core. The apparatus also includes a coil between the ferromagnetic core and the object.

A unit and a tactile sensation providing apparatus which enable simplification of the assembly process of the apparatus are provided. The unit is provided with an actuator, a first fixing unit fixable to a base, a second fixing unit, and an elastic member configured to couple the first fixing unit and the second fixing unit together. The second fixing unit is fixable to a vibration object and coupled to the actuator.

A unit and a tactile sensation providing apparatus which enable simplification of the assembly process of the apparatus are provided. The unit is provided with an actuator, a first fixing unit fixable to a base, a second fixing unit, and an elastic member configured to couple the first fixing unit and the second fixing unit together. The second fixing unit is fixable to a vibration object and coupled to the actuator.

Provided is an actuator having a piezoelectric element, a diaphragm to which the piezoelectric element is bonded and vibrates according to expansion and contraction displacement of the piezoelectric element, and a first spacer and a second spacer configured to fix both ends of the diaphragm in expansion and contraction displacement direction of the piezoelectric element to a base member. The driving characteristics of the actuator are determined by an effective length of the diaphragm between the first spacer and the second spacer.

A magnetostrictive alternator configured to convert pressure waves into electrical energy is provided. It should be appreciated that the magnetostrictive alternator may be combined in some embodiments with a Stirling engine to produce electrical power. The Stirling engine creates the oscillating pressure wave and the magnetostrictive alternator converts the pressure wave into electricity. In some embodiments, the magnetostrictive alternator may include aerogel material and magnetostrictive material. The aerogel material may be configured to convert a higher amplitude pressure wave into a lower amplitude pressure wave. The magnetostrictive material may be configured to generate an oscillating magnetic field when the magnetostrictive material is compressed by the lower amplitude pressure wave.

Systems and methods for detecting corrosion in pipes are disclosed herein. In one embodiment, an apparatus for detecting corrosion in an object includes an electromagnetic acoustic transducer (EMAT) having a ferromagnetic core and a plurality of permanent magnets arranged peripherally around the ferromagnetic core. The permanent magnets are arranged to produce a magnetic field through the ferromagnetic core. The apparatus also includes a coil between the ferromagnetic core and the object.

An EMAT system (1) for detecting surface and internal discontinuities (2) in thick conductive structures (90) at high temperatures, comprising a magnet (4) that generates a static magnetic field (SMF) and an HF electric coil (6) for inducing, or being induced by, eddy currents in the material (14). It comprises a perforated matrix-array laminated magnetic core (22) placed between the HF electric coil (6) and the inspected material (3), which is made up of a multitude of apertured HF active laminae (29) incorporating a ferromagnetic material, and of apertured insulating passive laminae (53). Trough-holes (41, 57) are drilled through each lamina (29, 53) and form a grooved cylindrical aperture (39). Parallel induced-current loops (43) encircle each magnetic trough-hole (41) of the HF active laminae (29). Cooling means (58) force a heat-transfer fluid (60) to pass through the grooved cylindrical aperture (39).

The invention relates to a device for transmitting mechanical vibrations to flowable media. The device is characterized in that the normal amplitudes of the effective surface points of a resonator are substantially uniform during a resonant vibration, and an amplitude vector in the effective surface points of more than 50 percent of an effective surface is not substantially parallel to the normal vector of these effective surface points.

The invention relates to a device for transmitting mechanical vibrations to flowable media. The device is characterized in that the normal amplitudes of the effective surface points of a resonator are substantially uniform during a resonant vibration, and an amplitude vector in the effective surface points of more than 50 percent of an effective surface is not substantially parallel to the normal vector of these effective surface points.

Disclosed is a vibration generator for shoes, including: a flat vibration plate having a length longer than the width thereof; support pieces horizontally protruding in the widthwise direction of the vibration plate; upper and lower casings coupled while restricting each end portion of each support piece, so as to accommodate the vibration plate therein; core magnets fixedly provided in one or more places among the respective end portions in the lengthwise direction of the vibration plate; upper magnets fixed to the upper casing so as to face the core magnets, thereby generating a repulsive force; and bottom magnets fixed to the lower casing so as to face the core magnets, thereby generating a repulsive force.