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.

Maximum-likelihood parameter estimation for unsupervised stochastic model-based image segmentation

Abstract: An unsupervised stochastic model-based approach to image segmentation is described, and some of its properties investigated. In this approach, the problem of model parameter estimation is formulated as a problem of parameter estimation from incomplete data, and the expectation-maximization (EM) algorithm is used to determine a maximum-likelihood (ML) estimate. Previously, the use of the EM algorithm in this application has encountered difficulties since an analytical expression for the conditional expectations required in the EM procedure is generally unavailable, except for the simplest models. In this paper, two solutions are proposed to solve this problem: a Monte Carlo scheme and a scheme related to Besag's (1986) iterated conditional mode (ICM) method. Both schemes make use of Markov random-field modeling assumptions. Examples are provided to illustrate the implementation of the EM algorithm for several general classes of image models. Experimental results on both synthetic and real images are provided. >

Vane assembly and temperature control arrangement

Abstract: A gas turbine engine vane assembly of the type adapted for use in an annular row of such assemblies and having spaced inner and outer platform portions for defining an annular hot gas stream flow path and a hollow airfoil extending therebetween. The airfoil is compartmentalized by a bridge member extending between the airfoil sidewalls and an impingement insert is provided for each compartment. Chordwise extending structural ribs are provided internally of the airfoil to strengthen the sidewalls and impingement baffles are provided outwardly of the platform portions for temperature control of these elements. Passageways are provided through the platforms to direct coolant to the downstream edges thereof and into the hot gas stream at an angle approximating the hot gas swirl angle.

Phosphors for white light generation from UV emitting diodes

Abstract: Ca 8 Mg(SiO 4 ) 4 Cl 2 :Eu 2+ ,Mn 2+ and Y 2 O 3 :Eu 3+ ,Bi 3+ are phosphors which have been sensitized to absorb ultraviolet radiation, such as from a light emitting diode, and to convert the radiation into visible light. A phosphor conversion material blend comprises Ca 8 Mg(SiO 4 ) 4 Cl 2 :Eu 2+ ,Mn 2+ ; Y 2 O 3 :Eu 3+ ,Bi 3+ , and known blue phosphors that absorb ultraviolet radiation from a LED and convert the radiation into visible bright white light. Also, a light emitting assembly comprises at least one of a red, green and blue phosphor for absorbing and converting ultraviolet radiation into visible light. A laser diode can be used to activate the phosphors to provide improved efficiency and brightness.