Nodes in an MC-LAG cluster communicate to synchronize and negotiate automatic switchovers (failover). Some implementations may support administrator-initiated (manual) switchovers. The diagram here shows four configurations: Illustration comparing LAG to high-availability MLAG # Switches A and B are each configured to group four discrete links (as indicated in green) into a single logical link with four times the bandwidth. Standard LACP protocol ensures that if any of the links go down, traffic will be distributed among the remaining three.
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Former logo used from 1999 until September 2009. This version used the ABC logo from 2007. WPBF first went on-the-air January 1, 1989, owned by Alan Potamkin and the John H. Phipps Company.Instant TV WPBF, New ABC Affiliate Starting From Scratch, Races Toward Sunday Air Debut, South Florida Sun-Sentinel, December 30, 1988.Fanfare Absent As Switchovers Strike Airwaves In S. Florida, South Florida Sun-Sentinel, January 2, 1989. This marked a return to West Palm Beach for Phipps, which had previously owned NBC affiliate WPTV-TV (channel 5) from 1956 to 1961.
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Regional Railways branding on an in-train poster, still displayed by default in 2007 British Rail was the brand image of the nationalised railway owner and operator in Great Britain, the British Railways Board, used from 1965 until its breakup and sell-off from 1993 onwards. From an initial standardised corporate image, several sub-brands emerged for marketing purposes, and later in preparation for privatisation. These brands covered rail networks, customers services, and several classes of new trains. With the size of British Rail's fleet, due to the time required to repaint rolling stock, in terms of the physical trains brand switchovers could be lengthy affairs lasting years.
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In 1965, with lobbying from British industries and the prospects of joining the Common Market, the government set a 10-year target for full conversion, and created the Metrication Board in 1969. Metrication did occur in some areas during this time period, including the re-surveying of Ordnance Survey maps in 1970, decimalisation of the currency in 1971, and teaching the metric system in schools. No plans were made to make the use of the metric system compulsory, and the Metrication Board was abolished in 1980 following a change in government. The United Kingdom avoided having to comply with the 1989 European Units of Measurement Directive (89/617/EEC), which required all member states to make the metric system compulsory, by negotiating derogations (delayed switchovers), including for miles on road signs and for pints for draught beer, cider, and milk sales.
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The Class 373 used for international high- speed rail services operated by Eurostar through the Channel Tunnel runs on overhead wires at 25 kV AC for most of its journey, with sections of 3 kV DC on Belgian lines between the Belgian high speed section and Brussels Midi station or 1.5 kV DC on the railway lines in the south of France for seasonal services. As originally delivered, the Class 373 units were additionally fitted with 750 V DC collection shoes, designed for the journey in London via the suburban commuter lines to Waterloo. A switch between third-rail and overhead collection was performed while running at speed, initially at Continental Junction near Folkestone, and later on at Fawkham Junction after the opening of the first section of the Channel Tunnel Rail Link. Between Kensington Olympia railway station and North Pole depot, further switchovers were necessary.
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If the device were made to record progressive scanned video, the switchover of the heads would fall in the middle of the picture and appear as a horizontal band. Interlacing allows the switchovers to occur at the top and bottom of the picture, areas which in a standard TV set are invisible to the viewer. The device can also be made more compact than if each sweep recorded a full frame, as this would require a double diameter drum rotating at half the angular velocity and making longer, shallower sweeps on the tape to compensate for the doubled line count per sweep. However, when a still image is produced from an interlaced video tape recording, on most older consumer grade units the tape would be stopped and both heads would just repeatedly read the same field of the picture, essentially halving the vertical resolution until playback proceeds.
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