Abstract: The present invention discloses a method, apparatus and software for determining a relative measure of the risk of faults in a built product relative to a reference build of the product. The measure can be based on a balance between the additional risk added as a result of changes made in a given build and the risk reduction resulting from testing applied to the build. The product associated with the builds can be a software product, a firmware product, an electronic device, and/or any manufactured product.

Abstract: The present invention discloses a method, apparatus and software for determining a relative measure of the risk of faults in a built product relative to a reference build of the product. The measure can be based on a balance between the additional risk added as a result of changes made in a given build and the risk reduction resulting from testing applied to the build. The product associated with the builds can be a software product, a firmware product, an electronic device, and/or any manufactured product.

Abstract: The apparatus comprises an object for display, a retro-reflector receiving light from the object, a beam-splitter in a path for light from the object to the retro-reflector, and a Fresnel lens (having no point of central symmetry) between the beam-splitter and the retro-reflector. The beam-splitter makes an oblique angle to the direction of propagation of the light, such that it transmits some light and reflects the rest. Light from the beam-splitter passes through the lens to the retro-reflector, which reflects it back through the lens to the beam-splitter. This retro-reflected light is reflected and/or transmitted by the beam-splitter to form a real image suspended in space. The type of Fresnel lens used in the apparatus improves viewability because unwanted reflections from the surfaces of the lens are shifted such that they are no longer visible when viewing the suspended image.

Abstract: Apparatus for displaying an image suspended in space comprises an object (1) for display, a retroreflector (2) receiving light from the object, a beamsplitter (3) in a path for light from the object to the retroreflector, and a concave mirror (4) between the beamsplitter and the retroreflector. The beamsplitter makes an oblique angle to the direction (6) of propagation of the light such that it transmits some light. Light from the beamsplitter is reflected by the mirror to the retroreflector which reflects it back via the mirror to the beamsplitter. This retroreflected light is reflected by the beamsplitter to form a real image (5) suspended in space. The use of a concave mirror improves viewability over apparatus including a converging lens because unwanted reflections from the surfaces of the lens are eliminated.

Abstract: In an overhead electric transmission system in which the phase conductors incorporate optical fibres, a joint between optical fibres of two phase conductors or between optical fibres of a phase conductor and an optical cable extending to a sub-station is enclosed within a fluid-tight metal housing. The housing is electrically connected to each phase conductor, is electrically insulated from earth, and has an external shape of such a form as to provide effective control of electrical stress. Preferably the metal housing is of hemi-spherical shape and is mounted on top of a porcelain insulator containing oil under pressure. Where an optical fibre connected at the joint is that of an optical cable, it passes into the metal housing through the oil filled porcelain insulator.