Abstract: An electrically insulating gas composition comprises C3F7CN, in an amount between 22% and 70% by volume and one or more inert gas selected from the list consisting of nitrogen, carbon dioxide (CO2), air and argon.

Abstract: An electrically insulating cross-arm for a tower for high-voltage power networks. The cross-arm includes an insulating structural member for attachment to the tower body and to support a conductor cable. The insulating structural member comprises a solid rigid spine extending along a long axis having cross sectional profile, normal to the long axis, having a second moment of area of its cross sectional profile about every axis normal to the long axis and dissecting its centroid has a value of A2/2? or more, where A is the area of the cross sectional profile. The structural member provides resistance to bending and compressive buckling and allows conductors to be safely supported at reduced tower height. T and Y shaped cross sections provide water run-off and inhibition of organic growth. The structural members are also generally useful as insulator members in high voltage power networks.

Abstract: An electrically insulating cross-arm for a tower for high-voltage power networks. The cross-arm includes an insulating structural member for attachment to the tower body and to support a conductor cable. The insulating structural member comprises a solid rigid spine extending along a long axis having cross sectional profile, normal to the long axis, having a second moment of area of its cross sectional profile about every axis normal to the long axis and dissecting its centroid has a value of A2/2? or more, where A is the area of the cross sectional profile. The structural member provides resistance to bending and compressive buckling and allows conductors to be safely supported at reduced tower height. T and Y shaped cross sections provide water run-off and inhibition of organic growth. The structural members are also generally useful as insulator members in high voltage power networks.

Abstract: An insulating composition for use in high voltage devices is formed from a soft dielectric casting compound, such as a silicone gel, comprising ferroelectric particles such as barium titanate dispersed within it. Low levels of particles, from 1% to 20% by volume of the insulating composition, are highly effective yet do not cause excessive thickening of the soft dielectric casting compound when it is in its liquid state. The insulating composition is particularly effective for coating, enrobing or encapsulating alternating high voltage devices such as power electronics devices in order to prevent electrical discharge.

Abstract: A method for managing contents of a web site. A request to access a web site is received from a requestor, wherein the web site comprises a sparse tree directory comprising elements used to build the web site. The sparse tree directory comprises a web site page hierarchy located at the root directory of a shape hierarchy, wherein the web site page hierarchy comprises a directory structure of the web application and the shape hierarchy defines user shapes accommodated by the web application. The sparse tree directory also comprises a first subdirectory corresponding to a first value of a dimension and a second subdirectory corresponding to a second value of the dimension, wherein the first subdirectory comprises a first element and the second subdirectory comprises a second element. A shape of the requestor is generated, wherein the shape defines elements that can be accommodated by the requestor. The sparse tree directory is cached. The sparse tree directory is searched for elements defined by the shape.

Abstract: A method for managing contents of a web site. A request to access a web site is received from a requester, wherein the web site comprises a sparse tree directory comprising elements used to build the web site. The sparse tree directory comprises a web site page hierarchy located at the root directory of a shape hierarchy, wherein the web site page hierarchy comprises a directory structure of the web application and the shape hierarchy defines user shapes accommodated by the web application. The sparse tree directory also comprises a first subdirectory corresponding to a first value of a dimension and a second subdirectory corresponding to a second value of the dimension, wherein the first subdirectory comprises a first element and the second subdirectory comprises a second element. A shape of the requestor is generated, wherein the shape defines elements that can be accommodated by the requester. The sparse tree directory is cached. The sparse tree directory is searched for elements defined by the shape.

Abstract: A method for managing contents of a web site. A request to access a web site is received from a requestor, wherein the web site comprises a sparse tree directory comprising elements used to build the web site. The sparse tree directory comprises a web site page hierarchy located at the root directory of a shape hierarchy, wherein the web site page hierarchy comprises a directory structure of the web application and the shape hierarchy defines user shapes accommodated by the web application. The sparse tree directory also comprises a first subdirectory corresponding to a first value of a dimension and a second subdirectory corresponding to a second value of the dimension, wherein the first subdirectory comprises a first element and the second subdirectory comprises a second element. A shape of the requestor is generated, wherein the shape defines elements that can be accommodated by the requestor. The sparse tree directory is cached. The sparse tree directory is searched for elements defined by the shape.