Abstract: A compact hybrid actuator has a fluid pump (20) arranged to supply fluid to an actuator (44). The pump has at least one electrically-powered solid-state pump driver (21) provided with a displacement element (22). The position of this displacement element modulates the volume of a fluid chamber (23). A driven valve (24) is operatively arranged to control the flows of fluid with respect to the pump chamber, and has one member (29) movable relative to a body (28) to modulate the opening of ports (25, 26) so as to form at least one three-way valve. A valve driver (31) is operatively arranged to operate the driven valve. Electrical power is provided to each valve and to the valve driver so as to operate these various elements in synchronism with one another. The improved pump driver and driven valve may be operated at frequencies in excess of 1 kHz.

Abstract: A compact hybrid actuator has a fluid pump (20) arranged to supply fluid to an actuator (44). The pump has at least one electrically-powered solid-state pump driver (21) provided with a displacement element (22). The position of this displacement element modulates the volume of a fluid chamber (23). A driven valve (24) is operatively arranged to control the flows of fluid with respect to the pump chamber, and has one member (29) movable relative to a body (28) to modulate the opening of ports (25, 26) so as to form at least one three-way valve. A valve driver (31) is operatively arranged to operate the driven valve. Electrical power is provided to each valve and to the valve driver so as to operate these various elements in synchronism with one another. The improved pump driver and driven valve may be operated at frequencies in excess of 1 kHz.

Abstract: A non-invasive apparatus and method are disclosed for measuring intracranial pressure. The intracranial measurement system transmits acoustic signals through a cranium and provides an indication of intracranial pressure based on the received acoustic signals after interaction with the brain. Properties such as acoustic transmission impedance, resonant frequency, resonance characteristics, velocity of sound and the like may be measured and correlated with intracranial pressure. The acoustic signals have typical frequencies of less than 100 kHz, for example, in the audible and sub-audible frequency ranges. The intensity of the transmitted acoustic signals used to determine intracranial pressure is relatively low, resulting in little or no health risks during short term or long term monitoring.

Abstract: A Peierls transition far-infrared radiation source comprised of a block of an organic one dimensional metal stressed at the ends and having a potential difference applied.

Abstract: A method and apparatus for controlling a chemical reaction by heterogeneous catalysis, in which a surface acoustic wave (SAW) is propagated along a surface of a piezoelectric element in contact with liquid or gaseous substances to be chemically reacted, to thus generate an electric field at the surface of the element which initiates and sustains the desired reaction. The catalysis rate can be varied by varying the frequency and/or intensity of the surface acoustic wave. The surface of the element may be coated with a very thin film of a catalytic group 8 metal which can be penetrated by the SAW electric field. In such an embodiment, normal catalysis proceeds via chemisorption, and the SAW element field acts to increase the catalysis rate.