General Electric

About: General Electric is a company organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Turbine & Signal. The organization has 76365 authors who have published 110557 publications receiving 1885108 citations. The organization is also known as: General Electric Company & GE.

A Theory of Liquid Surface Rupture by a Uniform Electric Field

Abstract: Surface distortion and rupture permits field emission from liquid surfaces at field strengths less than those effective for equally smooth solid surfaces. An approximate mathematical theory of the rupture of a plane liquid surface in a uniform electric field has been developed. The relation between initial distortion, rupture time, and field strength has been calculated for fields large compared to that which just renders the surface unstable. This critical field is ${E}_{m}=2{\ensuremath{\pi}}^{\frac{1}{2}}{(\ensuremath{\rho}gT)}^{\frac{1}{4}}=53$ kv ${\mathrm{cm}}^{\ensuremath{-}1}$ for mercury, where $\ensuremath{\rho}$ is density and $T$ is surface tension. Typically, the theory shows that a hump initially 4\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}5}$ cm high and of diameter 9\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$ cm will lead to rupture in 5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ sec. in a field of ${10}^{6}$ v ${\mathrm{cm}}^{\ensuremath{-}1}$. Relative to initial humps in the surface whose linear dimensions vary inversely as the square of the field, the time to rupture varies inversely as the cube of the field strength. This calculation shows that a lowered sparking potential to liquid mercury can be ascribed to surface rupture and shows that it is possible that surface rupture plays a part in Beams' low field emission from liquid mercury. Possible application of the theory to the high field condition at the cathode spot of the Hg arc is not clear.

Fabrication of components by layered deposition

Abstract: A component is fabricated by depositing a succession of overlying beads of a material, the pattern and position of the beads being assigned the proper characteristics of the corresponding section of the desired component. Shape definition is accomplished by characterizing the component as a series of sections or slices having the thickness of the bead, and programming a computer-controlled deposition head to deposit a succession of beads with the respective patterns and positions. Deposition is preferably by precision laser welding. Complex shapes having properties comparable to properties of forged or cast material are readily prepared. The material used in successive beads may be varied, producing a component of graded composition to achieve particular properties in various regions.

Glass reinforced polyester resins containing polytetrafluoroethylene and flame retardant additives

Abstract: Flame retardant thermoplastic molding compositions are provided comprising a normally flammable linear polyester, filamentous glass, a flame retardant agent and a polytetrafluoroethylene resin. The use of the polytetrafluoroethylene resin controls dripping and permits the flame retardant agent to be used in amounts sufficient to render the compositions non-burning or self-extinguishing without detracting from their physical properties.

Vertical double diffused metal oxide semiconductor VDMOS device with increased safe operating area and method

Abstract: A power field effect device has a gate grid having a plurality of elongate openings therein through which a base region forming a high voltage blocking junction with the underlying body was diffused. The openings have round ends in order to prevent the formation of spherical portions in the high voltage blocking junction. The round ends of adjacent openings are positioned close enough to each other that their diffusion regions merge, thereby raising the device breakdown voltage to that of the cylindrical junction portion along the straight edges of the junction. In an alternative embodiment, the openings do not have round ends and are positioned close enough together that their diffusions merge end to end.

Data compression system including successive approximation quantizer

Abstract: A data processing system augments compression of non-zero values of significant coefficients by coding entries of a significance map independently of coding the values of significant non-zero coefficients. A dedicated symbol represents a zerotree structure encompassing a related association of insignificant coefficients within the tree structure. The zerotree symbol represents that a coefficient is a root of a zerotree if, at a threshold T, the coefficient and all of its descendants that have been found to be insignificant at larger thresholds have magnitudes less than threshold T. The zerotree structure is disclosed in the context of a pyramid-type image subband processor together with successive refinement quantization and entropy coding to facilitate data compression.