Shields

About: Shields is a research topic. Over the lifetime, 1456 publications have been published within this topic receiving 10896 citations.

Stethoscope shield system and method of shielding stethoscope using the same

Abstract: A stethoscope shield system comprising a plurality of substantially planar shield stacked one upon the other with an adhesive disposed there between, each of the shields including a first surface having the adhesive applied thereto and a second surface such that adjacent shields adhere to one another with the first surface of each of these shields adhenng to the second surface of an adjacent shield with a first shield of the plurality of shields being adhered to the diaphragm of the stethoscope for supporting the stacked shields, wherein the adhesive disposed between the stacked shields has at least one of a consecutively increasing bonding area and a consecutively increasing adhesive bonding strength, and an exposed shield of the stacked shields is removed after contacting the body of a patient.

Electrostatic shielding of disc windings

Abstract: An electrostatic shielding arrangement for improving the initial distribution of voltage which in turn reduces the insulation stresses on disc-wound coils resulting from the application of impulse or steep wave-front voltages to such coils. Floating electrostatic shields are placed near or internal of the innermost or the innermost and outermost turns only of a disc coil section. Shields are connected together in pairs, with no more than one shield connection being made between adjacent coil sections.

An Equivalent Surface Source Method for Computation of the Magnetic Field Reduction of Metal Shields

Abstract: A numerical method for computation of the resultant quasi-static magnetic field in the vicinity of parallel wires and metal shields is presented. The primary magnetic field source is time-harmonic currents in wires. This field is modified by conducting magnetic and/or nonmagnetic shields. The material is assumed to be linear under the applied source field. The shielding effectiveness can be estimated by a comparison between the primary and the resultant field. The reaction magnetic field is expressed by a sum of fields caused by equivalent single- and double-layer sources distributed on the shield surface. Integral equations for unknown distributions of these equivalent sources are derived from the Green's second identity implemented inside and outside the shields. These equations are coupled integral equations, and are solved by the moment method. Numerical results of the resultant (shielded) magnetic field obtained with the proposed method are compared with the results of: 1) analytically solvable problems; 2) measurements; and 3) two different numerical methods.

Magnetostatic simulations for design of superconducting magnetic shields

Abstract: A magnetostatic approach to numerical simulations of magnetic field attenuation by superconducting shields is demonstrated on simple geometries. Comparisons to published measurements and analytic calculations show that results are accurate for simulation of a shield in the shape of a cylindrical tube. The capabilities of the method are shown by simulations which close the cylinder with end caps having access ports or gaps. With end caps having cylindrical ports, the simulated attenuation transits smoothly between the analytical results for semi-infinite tubes of the two radii. Radial gaps between solid end caps and the cylinder allow little flux leakage for time-varying fields, but significant leakage for static fields.

Electrical inductive apparatus having non-magnetic flux shields

Abstract: The electrical inductive apparatus including non-magnetic flux shields constructed of strips of highly electrically conductive material which are arranged to form a continuous loop around the core window. The shields are disposed parallel to the laminations of the magnetic core and adjacent the top and bottom surfaces of the core. Current induced in the shields by the leakage flux from the windings produces an opposing flux which prevents substantially all of the winding leakage flux from entering the magnetic core.