1.
Alstom
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A merger with parts of the General Electric Company plc formed GEC-Alstom in 1989, the company became Alstom in 1998. In 2014, Alstom and General Electric announced that a US$17 billion bid for the power and grid divisions had been made. The GE acquisition deal for the power and grid division was accepted by EU and US anticompetition authorities in mid 2015, in 1932, Alsthom expanded into transportation by acquiring Constructions Electriques de France, Tarbes, a manufacturer of electric locomotives as well as electrical and hydraulic equipment. In 1969, Compagnie Générale dElectricité became the majority shareholder of Alsthom, in 1976, Alsthom merged with Chantiers de lAtlantique, becoming Alsthom Atlantique. Thus, the business expanded into marine, the next year, it constructed the first 1300 MW generator set for the Paluel power station, setting a world record with an output of 1500 MW. In 1978, Alsthom delivered its first TGV to SNCF, the TGV went on to break world rail speed records in 1981 and in 1990. It also set the endurance record for high-speed train lines in 2001. In 1986, Alsthom Belfort received an order from EDF for the largest gas turbine in the world, in 1988–89, holding company CGEE Alstom acquired ACEC Energie and ACEC Automatisme from the dissolution of Belgian electrical engineering company ACEC SA. Alstom acquired 100% of ACECs transport division, renaming it ACEC Transport, in 1991, Alstoms parent company CGE was renamed Alcatel Alsthom Compagnie Générale dElectricité, or Alcatel Alsthom for short. In 1994, GEC Alsthom acquired the vehicle manufacturer Linke-Hofmann-Busch from Salzgitter AG. In 1995, the acquired the remaining shares in the steam turbine manufacturer MAN Energie. In early 1998, GEC Alsthom acquired the electrical contractor Cegelec, in 1998, GEC-Alsthom bought Italian firm SASIB SpAs rail signalling subsidiary Sasib Railways, which included the former General Railway Signal. In June 1998, GEC Alsthom was listed on the Paris Stock Exchange, GEC, at the same time, the company name was changed to Alstom. In 1999, Alstoms energy division merged with ABB in a 50–50 joint company known as ABB Alstom Power, Alstom also bought Canadas Télécité, a passenger information and security solutions company, and sold its heavy-duty gas turbine business to General Electric. The next year, it bought out ABBs share in ABB Alstom Power, in 2000, Alstom sold its diesel engine businesses to MAN Group. It also acquired a 51% stake in Fiat Ferroviaria, the Italian rail manufacturer, in April 2003, Alstom sold its industrial turbine business to Siemens for €1.1 billion. By 2003, Alstom was facing a crisis due to poor sales and over $5 billion of debt liabilities. Alstoms share price had dropped 90% over two years, in 2004, the French state took a 21% stake in Alstom and received an EU-approved French government bailout worth €2.5 billion
2.
London Underground 1959 Stock
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The 1959 Tube Stock was a type of London Underground tube train constructed in the late 1950s. They were intended for use on the Piccadilly line, but also saw use on several other tube lines and it was the first production tube stock to have unpainted aluminium alloy bodywork. The 1959 Stock was built by Metro-Cammell in Birmingham and were based on the prototype aluminium alloy bodied 1956 Stock. It operated at times on the Northern line, Bakerloo line, Central line. The units had a career, with some examples remaining in service until 2000. The 1959 Stock entered service on the Piccadilly line, but most units were drafted to the Central line because that lines Standard stock was becoming very unreliable, the Central lines version of the 1959 stock, the 1962 stock, later took over. The Piccadilly line extension to Heathrow, which opened in the early 1970s, therefore, the 1959 Stock was transferred to the Northern line between 1975 and 1979, allowing the scrapping of the oldest 1938 Stock on that line. The 1959 Stock also saw service on the Bakerloo line in the 1980s, when new, the 1959 stock was seen as distinctive because of the clean silver exterior. Over the years, however, the trains unpainted exteriors became jaded, the blue and grey interiors dated quickly. Stylistically the 1959 stock looked worn, but without the aesthetic red, by the mid-1990s these units were getting old and were in need of works attention. By this time, all the remaining 1959 Stock was concentrated on the Northern line, minor refurbishment of the stock took place, painting the blue/grey interiors white and replacing some of the seat moquettes. New trains in the form of 1995 Stock were built as replacements for both the 1959 stock and the 30 trains of 1972 stock also operating on the Northern line. Withdrawal of the 1959 Stock was an affair, and when the last example was withdrawn on 28 January 2000, it was the only remaining tube train to be crewed with a motorman. One unit was repainted in red and cream livery in 1990 to commemorate the lines 100th anniversary. Several vehicles have been preserved, at locations, including one complete 4-car unit. The complete list is shown below
3.
London Underground 1962 Stock
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The 1962 Tube Stock was a type of London Underground tube train built for use on the Central line. They were used on the Central line between 1962 and 1995, the 1962 Stock was built by Metro-Cammell and the BR Workshops in Derby for use on the Central line. Each unit consisted of four vehicles, two driving motors, an intermediate trailer, and an intermediate non-driving motor, formed DM + T + NDM + DM. A train usually consisted of two working in multiple. The 1962 Stock was ordered as a matter of urgency to replace the Standard Stock previously used on the Central line, two fires on Standard Stock units resulted in the hospitalisation of dozens of passengers. This experience, plus rapidly increasing numbers of breakdowns, hastened the need to replace these trains, the 1962 stock was ordered from Birmingham RC&W and from the British Railways workshops in Derby, a total of 619 cars. In 1961, BRCW asked to be relieved of their contract, as they were in difficulty, and the order was transferred to Metro-Cammell. The first 1962 stock train of 8 cars commenced service on 12 April 1962, the major improvement was the use of motor alternators for the auxiliary supplies using static rectification, instead of the motor generator sets. By the early 1990s, the 1962 Stock was due for replacement and this came in the form of the new 1992 Stock, which was developed from the prototype 1986 Stock. The last unit on the Central line was withdrawn on 17 February 1995, however, their use on the Northern line was short-lived, as they were soon replaced by the 1995 Stock, and the final unit was withdrawn on 11 November 1999. Several units remain in use as departmental vehicles, in addition, twelve cars were sold to the Epping Ongar Railway, but were scrapped after being destroyed by vandals while stabled at Ongar. One complete unit was preserved by Cravens Heritage Trains in 1995 and is being restored at Hainault depot, end view of 1962 Stock car,1978 Cravens Heritage Trains - owners of the preserved unit. Rolling Stock Summary Pictures on Flickr of this stock
4.
London Underground 1972 Stock
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The London Underground 1972 Stock is a type of rolling stock used on the London Underground. The 1972 Stock was ordered to make up the shortfall in trains on the Northern lines 1959 Tube Stock fleet and it is, however, currently used on the Bakerloo line. A total of 252 cars were ordered from Metro-Cammell and later refurbished by Tickford, in 2016, the 1972 stock started to have life extension work done to ensure the trains could remain in service. In the early 1970s the 1938 Tube stock on the Bakerloo and Northern lines was life-expired, tentative designs for a new Northern line fleet were abandoned when the go-ahead was given for the Piccadilly line to be extended to Heathrow Airport. That required a new fleet of trains to replace the 1959 stock then in use. Originally it was planned to refurbish some 301938 trains, the 1972 Tube stock was ordered in a hurry, so there was no time to create a new design, the trains were based on the 1967 Tube stock on the Victoria line. Although almost identical looking, the 1972 trains had a guard and door controls in the rear car, a further 33 trains of 1972 Tube stock were ordered to provide service on the Jubilee line. The 1972 Mk2 stock had slightly different interiors, such as dark blue seating moquette, externally the biggest difference was that the doors were painted red, with an LT roundel on the side of the carriages, rather than the Johnston lettering. The train number plates on the 1972 Mk2 trains operated on the Northern, the earlier 1972 stock on the Northern line was replaced by 1995 Tube Stock in 1999. The 1972 Mark 2 stock was refurbished in the 1990s. After being withdrawn from the Northern line, a few cars of 1972 Mark 1 stock were converted to run with 1967 stock in service on the Victoria line. A further two trains were converted to be compatible with the MkII type, and these now run on the Bakerloo line, one ex-Northern line Trainset is also permanently based at the now-closed Aldwych tube station, for use in films. The 1972 trains are formed of seven-car sets, and have a total of 268 passenger seats, the EVO tube concept design, a lighter articulated train with walk-through cars, was introduced early in 2011. In early 2014 the Bakerloo, Piccadilly, Central and Waterloo & City line rolling-stock replacement project was renamed New Tube for London and moved to the design and specification stage. The proposal introduces fully automated trains and signalling to increase capacity first on the Piccadilly line in 2025, followed by the Central, Waterloo & City, and Bakerloo lines by 2033. The fully automated trains may not have drivers, however, the ASLEF and RMT trade unions representing drivers strongly oppose this, middle two car are 67DM vehicles -3079,3179. Front 2 and rear two are 72 MK1 stock Front two 3313-4313 Rear two 4213-3213 Unit 3079 &3179 have recently been overhauled in Eastleigh, with no cab windows and new cables leading into each other. The AIT will replace the Track Recording Train which is currently in use, transport for London - Rolling Stock -1972 Tubeprune -1972 Tube Stock
5.
Northern line
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The Northern line is a London Underground line, coloured black on the Tube map. The section between Stockwell and Borough opened in 1890, and is the oldest section of deep-level tube line on the network, for most of its length it is a deep-level tube line. There were about 252,310,000 passenger journeys in 2011/12 on the Northern line, making it the second-busiest line on the Underground. Despite its name, it does not serve the northernmost stations on the network, though it does serve the southernmost station, there are 50 stations on the line, of which 36 have platforms below ground. An extension in the 1920s used a route planned by a fourth company. Abandoned plans from the 1920s to extend the line further southwards, from the 1930s to the 1970s, the tracks of a seventh company were also managed as a branch of the Northern line. The C&SLR, Londons first deep-level tube railway, was built under the supervision of James Henry Greathead and it was the first of the Undergrounds lines to be constructed by boring deep below the surface and the first to be operated by electric traction. The railway opened in November 1890 from Stockwell to a station at King William Street. This was inconveniently placed and unable to cope with the traffic so, in 1900. By 1907 the C&SLR had been extended at both ends to run from Clapham Common to Euston. The CCE&HR was opened in 1907 and ran from Charing Cross via Euston and Camden Town to Golders Green and it was extended south by one stop to Embankment in 1914 to form an interchange with the Bakerloo and District lines. In 1913 the Underground Electric Railways Company of London, owner of the CCE&HR, took over the C&SLR, during the early 1920s, a series of works was carried out to connect the C&SLR and CCE&HR tunnels to enable an integrated service to be operated. The first of new tunnels, between the C&SLRs Euston station and the CCE&HRs station at Camden Town, had originally been planned in 1912 but had been delayed by World War I. The second connection linked the CCE&HRs Embankment and C&SLRs Kennington stations and provided a new station at Waterloo to connect to the main line station there. The smaller-diameter tunnels of the C&SLR were expanded to match the diameter of the CCE&HR. In conjunction with the works to integrate the two lines, two extensions were undertaken, northwards to Edgware in Middlesex and southwards to Morden in Surrey. The Edgware extension used plans dating back to 1901 for the Edgware and it extended the CCE&HR line from its terminus at Golders Green to Edgware in two stages, to Hendon Central in 1923 and to Edgware in 1924. The line crossed open countryside and ran on the surface, apart from a tunnel north of Hendon Central
6.
Insulated-gate bipolar transistor
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The IGBT is a semiconductor device with four alternating layers that are controlled by a metal-oxide-semiconductor gate structure without regenerative action. Since it is designed to turn on and off rapidly, amplifiers that use it often synthesize complex waveforms with pulse-width modulation, the first-generation IGBTs of the 1980s and early 1990s were prone to failure through effects such as latchup and secondary breakdown. The current third-generation IGBTs are even better, with speed rivaling MOSFETs and this mode of operation was first proposed by Yamagami in his Japanese patent S47-21739, which was filed in 1968. This mode of operation was first experimentally reported in the four layer device by B. W. Scharf. This mode of operation was also discovered in vertical device in 1979 by B. Plummer filed a patent application for IGBT mode of operation in the four layer device in 1978, USP No.4199774 was issued in 1980 and B1 Re33209 was reissued in 1995 for the IGBT mode operation in the four layer device. Hans W. Becke and Carl F. Wheatley invented a device for which they filed a patent application in 1980. This patent has been called the seminal patent of the insulated gate bipolar transistor, the patent claimed no thyristor action occurs under any device operating conditions. This substantially means that the device exhibits non-latch-up IGBT operation over the device operation range. This additional p+ region creates a connection of a PNP bipolar junction transistor with the surface n-channel MOSFET. Practical devices capable of operating over a current range were first reported by Baliga et al. in 1982. A similar paper was submitted by J. P. Russel et al. to IEEE Electron Device Letter in 1982. However, it was demonstrated by Baliga and also by A. M. Goodman et al. in 1983 that the speed could be adjusted over a broad range by using electron irradiation. This was followed by demonstration of operation of the device at elevated temperatures by Baliga in 1985, complete suppression of the parasitic thyristor action and the resultant non-latch-up IGBT operation for the entire device operation range was achieved by A. Nakagawa et al. in 1984. The non-latch-up design concept was filed for US patents, to test the lack of latch-up, the prototype 1200V IGBTs were directly connected without any loads across a 600V constant voltage source and were switched on for 25 microseconds. The entire 600V was dropped across the device and a short circuit current flowed. The devices successfully withstood this severe condition and this was the first demonstration of so-called short-circuit-withstanding-capability in IGBTs. Non-latch-up IGBT operation was ensured, for the first time, for the device operation range
7.
Variable-frequency drive
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A variable-frequency drive is a type of adjustable-speed drive used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and voltage. VFDs are used in applications ranging from small appliances to the largest of mine mill drives and that lack of penetration highlights significant energy efficiency improvement opportunities for retrofitted and new VFD installations. VFDs are available in a number of different low- and medium-voltage AC-AC and DC-AC topologies, a variable-frequency drive is a device used in a drive system consisting of the following three main sub-systems, AC motor, main drive controller assembly, and drive/operator interface. The AC electric motor used in a VFD system is usually three-phase induction motor, motors that are designed for fixed-speed operation are often used. The VFD controller is a power electronics conversion system consisting of three distinct sub-systems, a rectifier bridge converter, a direct current link, and an inverter. Voltage-source inverter drives are by far the most common type of drives, most drives are AC-AC drives in that they convert AC line input to AC inverter output. However, in applications such as common DC bus or solar applications. The most basic rectifier converter for the VSI drive is configured as a three-phase, six-pulse, in a VSI drive, the DC link consists of a capacitor which smooths out the converters DC output ripple and provides a stiff input to the inverter. This filtered DC voltage is converted to quasi-sinusoidal AC voltage output using the active switching elements. VSI drives provide higher power factor and lower distortion than phase-controlled current-source inverter. The drive controller can also be configured as a phase converter having single-phase converter input, controller advances have exploited dramatic increases in the voltage and current ratings and switching frequency of solid-state power devices over the past six decades. Introduced in 1983, the bipolar transistor has in the past two decades come to dominate VFDs as an inverter switching device. For example, for 460 V,60 Hz motors, this linear V/Hz relationship is 460/60 =7.67 V/Hz, some V/Hz control drives can also operate in quadratic V/Hz mode or can even be programmed to suit special multi-point V/Hz paths. Although space vector pulse-width modulation is becoming popular, sinusoidal PWM is the most straightforward method used to vary drives motor voltage. Operation of the motors above rated nameplate speed is possible, but is limited to conditions that do not require more power than the rating of the motor. This is sometimes called field weakening and, for AC motors, means operating at less than rated V/Hz, permanent magnet synchronous motors have quite limited field-weakening speed range due to the constant magnet flux linkage. Wound-rotor synchronous motors and induction motors have much wider speed range, for example, a 100 HP,460 V,60 Hz,1775 RPM induction motor supplied with 460 V,75 Hz, would be limited to 60/75 = 80% torque at 125% speed = 100% power. At higher speeds, the motor torque has to be limited further due to the lowering of the breakaway torque of the motor
8.
Traction motor
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A traction motor is an electric motor used for propulsion of a vehicle, such as an electric locomotive or electric roadway vehicle. Direct-current motors with field windings were the oldest type of traction motors. These provided a speed-torque characteristic useful for propulsion, providing high torque at speeds for acceleration of the vehicle. By arranging the field winding with multiple taps, the speed characteristic could be varied, a further measure of control was provided by using pairs of motors on a vehicle, for slow operation or heavy loads, two motors could be run in series off the direct current supply. Where higher speed was desired, the motors could be operated in parallel, making a higher voltage available at each, parts of a rail system might use different voltages, with higher voltages in long runs between stations and lower voltage near stations where slower operation would be useful. A variant of the DC system was the AC operated series motor, since both the armature and field current reverse at the same time, the behavior of the motor is similar to that when energized with direct current. The AC system allowed efficient distribution of power down the length of a rail line, AC induction motors and synchronous motors are simple and low maintenance, but are awkward to apply for traction motors because of their fixed speed characteristic. An AC induction motor only generates useful amounts of power over a speed range determined by its construction. Traditionally road vehicles have used diesel and petrol engines with a mechanical or hydraulic transmission system, traditionally, these were series-wound brushed DC motors, usually running on approximately 600 volts. The availability of high-powered semiconductors has now made practical the use of much simpler, synchronous AC motors are also occasionally used, as in the French TGV. Before the mid-20th century, a large motor was often used to drive multiple driving wheels through connecting rods that were very similar to those used on steam locomotives. Examples are the Pennsylvania Railroad DD1, FF1 and L5 and the various Swiss Crocodiles and it is now standard practice to provide one traction motor driving each axle through a gear drive. Usually, the motor is three-point suspended between the bogie frame and the driven axle, this is referred to as a nose-suspended traction motor. The problem with such an arrangement is that a portion of the weight is unsprung, increasing unwanted forces on the track. In the case of the famous Pennsylvania Railroad GG1, two bogie-mounted motors drove each axle through a quill drive, the Bi-Polar electric locomotives built by General Electric for the Milwaukee Road had direct drive motors. The rotating shaft of the motor was also the axle for the wheels, by mounting the relatively heavy traction motor directly to the power cars frame rather than to the bogie, better dynamics are obtained allowing better high-speed operation. The DC motor was the mainstay of electric drives on both electric and diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. It consists of two parts, an armature and fixed field windings surrounding the rotating armature mounted around a shaft
9.
Bogie
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A bogie is a chassis or framework carrying wheels, attached to a vehicle, thus serving as a modular subassembly of wheels and axles. Bogies take various forms in various modes of transport, while bogie is the preferred spelling and first-listed variant in various dictionaries, bogey and bogy are also used. A bogie in the UK, or a truck, wheel truck. In Indian English, bogie may also refer to a railway carriage. In South Africa, the bogie is often alternatively used to refer to a freight or goods wagon. The first standard gauge British railway to build coaches with bogies, an alternate configuration often is used in articulated vehicles, which places the bogies under the connection between the carriages or wagons. Most bogies have two axles, but some cars designed for heavy loads have more axles per bogie, heavy-duty cars may have more than two bogies using span bolsters to equalize the load and connect the bogies to the cars. Suspension to absorb shocks between the frame and the rail vehicle body, Common types are coil springs, or rubber airbags. At least one wheelset, composed of an axle with bearings and a wheel at each end The bolster, the railway car is supported at the pivot point on the bolster. Axle box suspensions absorb shocks between the bearings and the bogie frame. The axle box suspension usually consists of a spring between the frame and axle bearings to permit up-and-down movement, and sliders to prevent lateral movement. A more modern design uses solid rubber springs, brake equipment, Two main types are used, brake shoes that are pressed against the tread of the wheel, and disc brakes and pads. More modern, bolsterless bogie designs omit these features, instead taking advantage of the movement of the suspension to permit rotational movement. The Commonwealth bogie, manufactured by the English Steel Corporation under licence from the Commonwealth Steel Company in Illinois, fitted with SKF or Timken bearings, it was introduced in the late 1950s for all BR Mark 1 vehicles. It was a heavy, cast-steel design weighing about 6.5 long tons, with sealed roller bearings on the axle ends, the leaf springs were replaced by coil springs running vertically rather than horizontally. The advanced design gave a better quality than the BR1. The side frame of the bogie was usually of bar construction, with simple horn guides attached, the axle boxes had a cast-steel equaliser beam or bar resting on them. The bar had two steel coil springs placed on it and the bogie frame rested on the springs, the effect was to allow the bar to act as a compensating lever between the two axles and to use both springs to soften shocks from either axle
10.
Adtranz
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ABB Daimler-Benz Transportation, commonly known under its brand Adtranz, was a multi-national rail transport equipment manufacturer with facilities concentrated in Europe and the US. The company was created in 1996 in the merger of Daimler-Benzs, in 1999, DaimlerChrysler bought ABBs shares and changed its official name to DaimlerChrysler Rail Systems. Bombardier Transportation acquired the company in 2001, at which time Adtranz was the second largest manufacturer of such equipment. The acquisition significantly increased the size of Bombardiers rail industry holdings making Bombardier the largest rail equipment manufacturer in the world, Adtranz manufactured mainline locomotives, high-speed, regional, metro and underground passenger trains, trams and people movers as well as freight wagons. Non rolling stock businesses included railway electrification and signalling infrastructure, in the EU, outside Germany, the merger would have meant no significant market share increase, including Scandinavia, where ABB had a dominant market share. The merger came into force on 1 January 1996, however the company continued to be loss making, losing $111 million in 1997. Polish manufacturer Pafawag was acquired in 1997 and the facility modernised, controlling interests in MÁV Dunakeszi, Hungary, a new diesel locomotive design with engine and electrical traction system provided by General Electric was introduced, named Blue Tiger. Adtranz intended to consolidate its product range around these families once on-going deliveries are finished, Adtranz continued to make an operating loss in 1998, attributed to earlier contracts with underestimated costs, as well as technical problems with products. The same year brought an order for 400 locomotives for Deutsche Bahn, in 2000 Adtranz finally achieved profitability. In preparation for a sale from DaimlerChrysler buyers for non-core rolling stock manufacturing businesses were sought, in January 2000 The Greenbrier Companies acquired the freight wagon business based in Siegen. The electrical installations business was sold to Balfour Beatty in late 2000 for €153million, no buyer was found for the railway signalling division. In August 2000 Bombardier Inc. announced that it was to buy Adtranz for $711million, the takeover came into legal effect on 1 May 2001 with a final price of $725million. The brand Adtranz was created by Landor Associates as part of the identity of ABB Daimler Benz Transportation. It was capitalised by the companies with a capital D as ADtranz, following the standard English text formatting, above the text ADtranz, the company logo included a green dot, symbolizing a signal set on green, as well as the environmental friendliness of railways. In addition to the company registered the slogan ADtranz - we speak railways. Rights on the brand and slogan were deleted in 2008 and 2007 respectively, westinghouse Transportation - via AEG acquisition 1988 Archive of Adranz homepage Welcome to Adtranz. Archived from the original on 28 December 1996
11.
London Underground infrastructure
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The infrastructure of the London Underground includes 11 lines, with 270 stations. Most of the lines emerge onto the surface outside the central area, the oldest train running on the Underground was introduced in 1972. The Underground is electrified using a system, the DC traction supply being independent of the running rails. Planned improvements include new stations, line extensions and more lines with automatic train operation, the total length of railway on London Underground is 250 miles and made up of the sub-surface network and the deep-tube lines. In 1971/72 it was remeasured in kilometres using Ongar as the zero point, the tunnels and trains are of a similar size to those on British main lines. The Hammersmith & City and Circle lines share all their stations and it is these that were the tube lines, although since the 1950s the term tube has come to be used to refer to the whole London Underground system. Many of the central London deep-tube line stations, such as the Central and Piccadilly lines, are higher than the lines to assist deceleration when arriving. There are 20 miles of tunnel and 93 miles of tube tunnel. Trains generally run on the track, although in some places, for example the Central line east of St Pauls station. Seven of the 32 London boroughs are not served by the Underground, six of these are south of the River Thames, Bexley, Bromley, Croydon, Kingston, Lewisham and Sutton. The seventh unserved borough is Hackney, although Manor House and Old Street stations lie just outside its boundary, the borough is served by the London Overgrounds North London Line and its East London Line extension. Greenwich borough was unserved until North Greenwich station opened on the Jubilee line extension in 1999, the borough of Lewisham used to be served by the Underground on the East London line - now part of London Overground - at New Cross and New Cross Gate. The lines are electrified with a four-rail DC system, a rail between the rails is energised at −210 V and a rail outside the running rails at +420 V. The traction current has no direct earth point, but there are two resistors connected across the traction supply, the centre tap of the resistors is earthed, establishing the reference point between the positive and negative rails by voltage division. The resistors are large enough to prevent large currents flowing through the earthed infrastructure, the positive resistor is twice as large as the negative resistor, since the positive rail carries twice the voltage of the negative rail. The Metropolitan Railways first line was built in the belief it would be operated by smokeless locomotives and this led to an 1897 Board of Trade report that reported a pharmacist was treating people in distress after having travelled on the railway with his Metropolitan Mixture. The report recommended more openings be authorised but the sections of the Metropolitan. Forced ventilation was not considered when the deep-tube Central London Railway opened in 1900, however, soon after opening there were complaints about a smell that the company couldnt explain, and by 1911 they had installed a system of fans injecting filtered air and ozone
12.
London Underground
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The London Underground is a public rapid transit system serving London and some parts of the adjacent counties of Buckinghamshire, Essex and Hertfordshire in the United Kingdom. The network has expanded to 11 lines, and in 2015–16 carried 1.34 billion passengers, the 11 lines collectively handle approximately 4.8 million passengers a day. The system has 270 stations and 250 miles of track, despite its name, only 45% of the system is actually underground in tunnels, with much of the network in the outer environs of London being on the surface. In addition, the Underground does not cover most southern parts of Greater London, the current operator, London Underground Limited, is a wholly owned subsidiary of Transport for London, the statutory corporation responsible for the transport network in Greater London. As of 2015, 92% of operational expenditure is covered by passenger fares, the Travelcard ticket was introduced in 1983 and Oyster, a contactless ticketing system, in 2003. Contactless card payments were introduced in 2014, the LPTB was a prominent patron of art and design, commissioning many new station buildings, posters and public artworks in a modernist style. Other famous London Underground branding includes the roundel and Johnston typeface, to prepare construction, a short test tunnel was built in 1855 in Kibblesworth, a small town with geological properties similar to London. This test tunnel was used for two years in the development of the first underground train, and was later, in 1861, the worlds first underground railway, it opened in January 1863 between Paddington and Farringdon using gas-lit wooden carriages hauled by steam locomotives. It was hailed as a success, carrying 38,000 passengers on the opening day, the Metropolitan District Railway opened in December 1868 from South Kensington to Westminster as part of a plan for an underground inner circle connecting Londons main-line termini. The Metropolitan and District railways completed the Circle line in 1884, built using the cut and this opened in 1890 with electric locomotives that hauled carriages with small opaque windows, nicknamed padded cells. The Waterloo and City Railway opened in 1898, followed by the Central London Railway in 1900, the Metropolitan Railway protested about the change of plan, but after arbitration by the Board of Trade, the DC system was adopted. When the Bakerloo was so named in July 1906, The Railway Magazine called it an undignified gutter title, by 1907 the District and Metropolitan Railways had electrified the underground sections of their lines. In January 1913, the UERL acquired the Central London Railway, the Bakerloo line was extended north to Queens Park to join a new electric line from Euston to Watford, but World War I delayed construction and trains reached Watford Junction in 1917. During air raids in 1915 people used the stations as shelters. An extension of the Central line west to Ealing was also delayed by the war, the Metropolitan promoted housing estates near the railway with the Metro-land brand and nine housing estates were built near stations on the line. Electrification was extended north from Harrow to Rickmansworth, and branches opened from Rickmansworth to Watford in 1925, the Piccadilly line was extended north to Cockfosters and took over District line branches to Harrow and Hounslow. In 1933, most of Londons underground railways, tramway and bus services were merged to form the London Passenger Transport Board, the Waterloo & City Railway, which was by then in the ownership of the main line Southern Railway, remained with its existing owners. In the same year that the London Passenger Transport Board was formed, in the following years, the outlying lines of the former Metropolitan Railway closed, the Brill Tramway in 1935, and the line from Quainton Road to Verney Junction in 1936
13.
Moorgate station
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Moorgate is a central London railway terminus and connected London Underground station on Moorgate in the City of London. The station was opened as Moorgate Street in 1865 by the Metropolitan Railway, in 1900 the City & South London Railway added the station to its network and the Great Northern & City Railway began serving the station in 1904. In 1975 the Northern City Line platforms were the site of the Moorgate tube crash in which 43 people were killed—the worst accident in the history of the London Underground, the station has entrances on both Moorgate itself and Moorfields, which runs parallel. While the public entrances from the street access to all the train services at the station. The Circle, Hammersmith & City and Metropolitan lines of the Underground system all use platforms 1 and 2, for terminating trains at busy times, there are platforms 3 and 4 which are west-facing bays. Adjacent to these are platforms 5 and 6 of the former Thameslink trains service from Bedford and these are disused following the closure of the Moorgate branch from Farringdon junction as part of the Thameslink programme and are now used for the storage of permanent way material. The Northern line of the Underground uses platforms 7 and 8, national Rail services on the Northern City Line use platforms 9 and 10, which are terminal platforms. Train services run via the East Coast Main Line to Welwyn Garden City, the station was opened by the Metropolitan Railway in December 1865 when it extended its original route between Paddington and Farringdon. Increasing traffic by other companies, including traffic, led to the line between Kings Cross and Moorgate being widened to four tracks in 1868, the route was called the City Widened Lines. Suburban services from the Midland Railway ran via Kentish Town and the Great Northern Railway ran via Kings Cross, the line was extended to Angel the following year. The Northern City Line to Moorgate was opened by the Great Northern & City Railway in February 1904 offering a service to Finsbury Park, the route was constructed in tube tunnels, but they were constructed at a diameter capable of accommodating main-line trains. Moorgate station was modernised at platform level and street level in the 1960s. The realignment of the platforms enabled about 500 yd of the line to Barbican to be straightened and moved south to facilitate development of the Barbican Estate and it was the greatest loss of life on the Underground during peacetime and the worst ever train accident on the system. The cause was the failure to stop, leading the train to run into the dead end tunnel before colliding with the buffers. British Rail took over control of the Northern City Line from London Underground in 1975, the Highbury Branch of the Northern line was terminated. Services from Finsbury Park to Moorgate were diverted to the Northern City Line from the City Widened Lines the following year, traction current on the Underground lines is supplied by the standard London Underground four rail system. Trains using the deep level Northern City Line platforms are supplied with 750 V DC traction current via the third rail, signalling is Track Circuit Block, Colour light signals with tripcock mechanisms, controlled by Kings Cross PSB. The former sub surface Thameslink bay platforms were equipped with 25 kV AC overhead line equipment, signalling was Track Circuit Block, Multiple aspect colour light signals, controlled by West Hampstead PSB
14.
Charing Cross tube station
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Charing Cross is a London Underground station at Charing Cross in the City of Westminster with entrances located in Trafalgar Square and The Strand. The station is served by the Northern and Bakerloo lines and provides an interchange with the National Rail network at Charing Cross station. On the Northern line it is between Embankment and Leicester Square stations on the Charing Cross branch, and on the Bakerloo line it is between Embankment and Piccadilly Circus stations, the station is in Travelcard Zone 1. The station was served by the Jubilee line between 1979 and 1999, acting as the terminus of the line during that period. For most of the history of the Underground the name Charing Cross was associated not with this station, the Northern line and Bakerloo line parts of the station were originally opened as two separate stations and were combined when the now defunct Jubilee line platforms were opened. The constituent stations also underwent a number of changes during their history. The first part of the complex, the Bakerloo line platforms, was opened as Trafalgar Square by the Baker Street & Waterloo Railway on 10 March 1906. The Northern line platforms were opened a year later, as Charing Cross, by the Charing Cross, at its opening this station was the southern terminus of the CCE&HR which ran to two northern termini at Golders Green and Highgate tube stations. The interchange station between the BS&WR and District had been known hitherto as Charing Cross and Embankment and these names lasted only a short time, on 9 May 1915, Charing Cross was renamed Strand and for Charing Cross the tube lines adopted the District Railway name of Charing Cross. At the same time, the separate Strand station on the Great Northern, Piccadilly, the Northern line Strand station was closed on 4 June 1973 to enable the construction of the new Jubilee line platforms. These platforms were constructed between the Bakerloo line and Northern line platforms together with the long-missing below-ground interchange between two lines. In anticipation of the new station, from 4 August 1974 Charing Cross was renamed Charing Cross Embankment. The West End branch of the Northern line has been known as the Charing Cross branch since before the 1979 renaming, and this name has continued despite the change of station to which it refers. Although Charing Cross was constructed as the terminus of the Jubilee line. The tunnels were constructed beyond the station beneath the Strand as far as 143 Strand. The tunnels also extend beyond the platforms into the Overrun, each overrun has the capacity to stable a further two trains each. As the Jubilee line platforms and track are maintained by TfL for operation reasons, they can also be used by film. In 2006, it was proposed that an extension to the Docklands Light Railway from Bank station would take over the platforms, intermediate stations at Aldwych and City Thameslink would be opened, mirroring the planned route of the old Fleet line
15.
Hampstead tube station
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Hampstead is a London Underground station in Hampstead, North London. The station is on the Edgware branch of the Northern line, the station is on the boundary between Travelcard Zone 2 and Zone 3. Designed by architect Leslie Green the station was opened on 22 June 1907 by the Charing Cross, Hampstead is on a steep hill and the station platforms are the deepest on the London Underground network, at 58.5 metres below ground level. It has the deepest lift shaft on the Underground at 55 metres which houses high-speed lifts and they were previously Otis lifts, but were modernised by Wadsworth lifts, & again in 2014 by small generic lift installer Accord. There is also an emergency staircase of over 320 steps. To the north, between Hampstead and Golders Green stations, is the uncompleted North End or Bull & Bush station, London Overgrounds Hampstead Heath station on the North London Line is a 10–15 minute walk east. London Buses routes 46 and 268, schools service 603 and night bus N5 serve the station, London Transport Museum Photographic Archive Station exterior,1925
16.
Clapham Common tube station
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Clapham Common is a London Underground station in Clapham within the London Borough of Lambeth. It is on the Northern line, between Clapham North and Clapham South stations, and is in Travelcard Zone 2. The station is at the tip of Clapham Common and was opened in June 1900 as the new southern terminus of the City & South London Railway. It remained the terminus until the Morden extension was opened in 1926, the station has two entrances, one at the west via a domed building dating from the 1920s, and one at the east via a modern curved-steel and glass pavilion. Clapham Common is one of two remaining stations on the underground that has an island platform in tunnel serving both the northbound and southbound lines, the other being Clapham North. Clapham Common is one of eight London Underground stations that have a deep-level air-raid shelter underneath them, both entrances to the shelter are north of the station on Clapham High Street. Train frequencies vary throughout the day, but generally operate every 2–6 minutes between 06,09 and 00,21 in both directions. The station is served by London Bus routes 35,37,50,88,137,155,249,322,345,417,689 and 690, and by night routes N35, N137 and N155. For 2 weeks in September 2016, all of the used in the station were replaced by photos of cats. This was a paid for on crowdfunding site Kickstarter and organized by an organisation called The Citizens Advertising Takeover Service. In January 2017, as part of the initiative Veganuary, PETA took over the station informing and encouraging commuters to adopt veganism for the month, London Transport Museum Photographic Archive Station in 1925
17.
Lord Mayor's Show
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The Lord Mayors Show is one of the best-known annual events in London as well as one of the longest-established, dating back to the 16th century. The Lord Mayor after whom the show is named is the Lord Mayor of the City of London, a city and ceremonial county within Greater London, the City is also Londons main modern financial district, widely known informally as the Square Mile. A new lord mayor is appointed every year and the parade that takes place as his or her inauguration ceremony reflects that this was once one of the most prominent offices in England. The position of Lord Mayor has a role within the City and is distinct from the position of Mayor of London, namely the elected head of the Greater London Authority. The Lord Mayors Show is centred on a parade which in its modern form is a light-hearted combination of traditional British pageantry. Until 1882 the procession went to Westminster Hall, originally this journey was mostly made by barge on the River Thames, the usual method of transport for this route in those days. In London, the show occurred annually on 29 October, in 1751, Great Britain replaced the Julian calendar with the Gregorian calendar, the Lord Mayors Show was then moved to 9 November. In 1959, another change was made, the Lord Mayors Show is now held on the second Saturday in November. The Lord Mayors Show has regularly held on the scheduled day, it has not been moved since 1852. The show was not interrupted by the Second World War, the Lord Mayor has been making that journey every year for 477 years, surviving plague and fire and countless wars and insurrections. The modern Lord Mayors procession is a descendant of that first journey to Westminster. See also Lord Mayor of Londons State Coach Formerly, the route was varied each year so that the procession could pass through the Lord Mayors home ward, since 1952, however, the route has been fixed. The Lord Mayor rode on horseback or went on a barge via the River Thames, the river transport for the Lord Mayors Show gave rise to the word float when used in the context of parades. More recently, Sir Murray Fox in 1974 had a model of a fox in the procession. Lord Mayor Gilbert Heathcote was unseated from his horse by a flower girl in 1710. A stand-in coach was used for years until 1856, the last occasion on which barges were used. In 1757 Sir Charles Asgill, a banker who became the next Lord Mayor, equates to around £120,000, but the replacement value has been estimated at £2 million. The side panels of the Lord Mayors State Coach were painted by Cipriani and it is pulled by six horses, two fewer than the Queens
18.
Alternating current
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Alternating current, is an electric current which periodically reverses direction, whereas direct current flows only in one direction. A common source of DC power is a cell in a flashlight. The abbreviations AC and DC are often used to mean simply alternating and direct, the usual waveform of alternating current in most electric power circuits is a sine wave. In certain applications, different waveforms are used, such as triangular or square waves, audio and radio signals carried on electrical wires are also examples of alternating current. These types of alternating current carry information encoded onto the AC signal and these currents typically alternate at higher frequencies than those used in power transmission. Electrical energy is distributed as alternating current because AC voltage may be increased or decreased with a transformer, use of a higher voltage leads to significantly more efficient transmission of power. The power losses in a conductor are a product of the square of the current and this means that when transmitting a fixed power on a given wire, if the current is halved, the power loss will be four times less. Power is often transmitted at hundreds of kilovolts, and transformed to 100–240 volts for domestic use, high voltages have disadvantages, such as the increased insulation required, and generally increased difficulty in their safe handling. In a power plant, energy is generated at a convenient voltage for the design of a generator, near the loads, the transmission voltage is stepped down to the voltages used by equipment. Consumer voltages vary somewhat depending on the country and size of load, the voltage delivered to equipment such as lighting and motor loads is standardized, with an allowable range of voltage over which equipment is expected to operate. Standard power utilization voltages and percentage tolerance vary in the different mains power systems found in the world, high-voltage direct-current electric power transmission systems have become more viable as technology has provided efficient means of changing the voltage of DC power. HVDC systems, however, tend to be expensive and less efficient over shorter distances than transformers. Three-phase electrical generation is very common, the simplest way is to use three separate coils in the generator stator, physically offset by an angle of 120° to each other. Three current waveforms are produced that are equal in magnitude and 120° out of phase to each other, if coils are added opposite to these, they generate the same phases with reverse polarity and so can be simply wired together. In practice, higher pole orders are commonly used, for example, a 12-pole machine would have 36 coils. The advantage is that lower rotational speeds can be used to generate the same frequency, for example, a 2-pole machine running at 3600 rpm and a 12-pole machine running at 600 rpm produce the same frequency, the lower speed is preferable for larger machines. If the load on a system is balanced equally among the phases. Even in the worst-case unbalanced load, the current will not exceed the highest of the phase currents
19.
Power inverter
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A power inverter, or inverter, is an electronic device or circuitry that changes direct current to alternating current. The input voltage, output voltage and frequency, and overall power handling depend on the design of the device or circuitry. The inverter does not produce any power, the power is provided by the DC source, a power inverter can be entirely electronic or may be a combination of mechanical effects and electronic circuitry. Static inverters do not use moving parts in the conversion process, a typical power inverter device or circuit requires a relatively stable DC power source capable of supplying enough current for the intended power demands of the system. The input voltage depends on the design and purpose of the inverter, examples include,12 VDC, for smaller consumer and commercial inverters that typically run from a rechargeable 12 V lead acid battery or automotive electrical outlet. 24,36 and 48 VDC, which are standards for home energy systems. 200 to 400 VDC, when power is from solar panels. 300 to 450 VDC, when power is from electric vehicle battery packs in vehicle-to-grid systems, hundreds of thousands of volts, where the inverter is part of a high-voltage direct current power transmission system. An inverter can produce a wave, modified sine wave, pulsed sine wave. The two dominant commercialized waveform types of inverters as of 2007 are modified sine wave and sine wave, the second method converts DC to AC at battery level and uses a line-frequency transformer to create the output voltage. This is one of the simplest waveforms an inverter design can produce and is best suited to low-sensitivity applications such as lighting and heating, square wave output can produce humming when connected to audio equipment and is generally unsuitable for sensitive electronics. A power inverter device which produces a multiple step sinusoidal AC waveform is referred to as a sine wave inverter, to more clearly distinguish the inverters with outputs of much less distortion than the modified sine wave inverter designs, the manufacturers often use the phrase pure sine wave inverter. However, this is not critical for most electronics as they deal with the quite well. Where power inverter devices substitute for standard power, a sine wave output is desirable because many electrical products are engineered to work best with a sine wave AC power source. The standard electric utility provides a sine wave, typically with minor imperfections, switch-mode power supply devices, such as personal computers or DVD players, function on quality modified sine wave power. AC motors directly operated on non-sinusoidal power may produce extra heat, may have different speed-torque characteristics, the modified sine wave output of such an inverter is the sum of two square waves one of which is phase shifted 90 degrees relative to the other. The result is three level waveform with equal intervals of zero volts, peak positive volts, zero volts, peak negative volts, the resultant wave very roughly resembles the shape of a sine wave. Most inexpensive consumer power inverters produce a sine wave rather than a pure sine wave
20.
Gate turn-off thyristor
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A gate turn-off thyristor is a special type of thyristor, which is a high-power semiconductor device. It was invented at General Electric, gTOs, as opposed to normal thyristors, are fully controllable switches which can be turned on and off by their third lead, the GATE lead. Normal thyristors are not fully controllable switches, thyristors can only be turned ON and cannot be turned OFF. Thyristors are switched ON by a signal, but even after the gate signal is de-asserted. Thus, a thyristor behaves like a semiconductor diode after it is turned on or fired. The GTO can be turned on by a signal. Turn on is accomplished by a current pulse between the gate and cathode terminals. As the gate-cathode behaves like PN junction, there will be relatively small voltage between the terminals. The turn on phenomenon in GTO is however, not as reliable as an SCR, turn off is accomplished by a negative voltage pulse between the gate and cathode terminals. This restricts the maximum switching frequency to approx 1 kHz and it may be noted however, that the turn off time of a GTO is approximately ten times faster than that of a comparable SCR. To assist with the process, GTO thyristors are usually constructed from a large number of small thyristor cells connected in parallel. Comparison of an SCR and GTO of same rating, a distributed buffer gate turn-off thyristor is a thyristor with additional PN layers in the drift region to reshape the field profile and increase the voltage blocked in the off state. Compared to a typical PNPN structure of a thyristor, this thyristor would be a PN-PN-PN type structure in here. GTO thyristors are available with or without reverse blocking capability, Reverse blocking capability adds to the forward voltage drop because of the need to have a long, low doped P1 region. GTO thyristors capable of blocking reverse voltage are known as Symmetrical GTO thyristors, usually, the reverse blocking voltage rating and forward blocking voltage rating are the same. The typical application for symmetrical GTO thyristors is in current source inverters, GTO thyristors incapable of blocking reverse voltage are known as asymmetrical GTO thyristors, abbreviated A-GTO, and are generally more common than Symmetrical GTO thyristors. They typically have a reverse breakdown rating in the tens of volts, A-GTO thyristors are used where either a reverse conducting diode is applied in parallel or where reverse voltage would never occur. GTO thyristors can be fabricated with a reverse conducting diode in the same package and these are known as RCGTO, for Reverse Conducting GTO thyristor
21.
British Rail Class 465
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The British Rail Class 465 Networker electric multiple units were built by GEC Alsthom and BREL between 1991 and 1993, and by ABB Rail between 1993 and 1994. They were brought into service from 1992 and operated by British Rail until 1997, then by Connex until 2003, South Eastern Trains until 2006 and then Southeastern to the present day. Network SouthEast began the planning for the development of the Class 465 Networker in 1988, the Class 465 was introduced in order to replace the 41-year-old Class 415 EMUs. All trains were supplied in Network SouthEast livery and branded Kent Link Networker. Some units were re-liveried in the first Connex South Eastern livery, all 465/0, 465/1, 465/2, 465/9 and 466 trains are now in the white and charcoal livery of Southeastern with blue doors. There are other visible but minor differences in door switches and audible chimes, window shapes, in addition, the two units employ different traction motors, which sound different. Despite the differences though, the units can be used interchangeably, particularly during peak times when longer trains are used, it is quite common to see a train comprising two four car units, one from each batch. Both classes share many similarities with the later dual-voltage Class 365, when first introduced, all seating was standard class only. Although the units are interoperable, the parts for the different units are different. The maximum speed of a Class 465 Networker is 75 mph, a Solid State Traction Converter package controls 3-phase AC Traction motors, which allows for Rheostatic or Regenerative Dynamic braking. Primary braking system is Electro-pneumatically actuated disc brakes, which is blended with the Dynamic brakes, tachometers on every axle of the unit provide for Wheel Slip/Slide Protection. A solid state Auxiliary Converter provides 110 V DC and 240 V AC supplies, on a BREL the Aux Converter is located on the TSO, whereas on the GEC Alsthom there is one each on the TSO and TSOL. In 2007, plans were drawn up to improve reliability of the BREL, brush, the suppliers / manufacturers of the original traction equipment worked as consultants to assist in retro-fitting the new equipment. The first example to re-enter service was 465181, which rolled out in March 2009, the units with the new equipment are easily recognisable, because they sound similar to the Class 395. In 2005,34 465/2 units were given an extensive refurbishment and this included new interior panelling, new flooring, new lighting, new seat moquette, and the addition of a new first class seating area at the front and rear of the units, amongst other changes. This was done with the intention that they would be cascaded to the outer-suburban routes alongside the Class 375s, from 2010, the whole of the class 465/466 saw another refresh, with new seating covers and Advertisement posters. It wasnt until 465151 was returned in early 2011 that we saw the livery which now seems to be standard. Since December 2010, the 465s have been returned to Slade Green Depot on a weekly basis and this process was finished on 21 May 2012 once all the 465/0/1s had been repainted
22.
Direct current
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Direct current is a flow of electrical charge carriers that always takes place in the same direction. The current need not always have the magnitude, but if it is to be defined as dc. This contrasts with alternating current which varies the direction of flow, sources of direct current include power supplies, electrochemical cells and batteries, and photovoltaic cells and panels. The intensity, or amplitude, of a direct current might fluctuate with time, in some such cases the dc has an ac component superimposed on it. An example of this is the output of a cell that receives a modulated light communications signal. A source of dc is sometimes called a dc generator, batteries and various other sources of dc produce a constant voltage. This is called pure dc and can be represented by a straight, the peak and effective values are the same. The peak to peak value is zero because the instantaneous amplitude never changes, in some instances the value of a dc voltage pulsates or oscillates rapidly with time, in a manner similar to the changes in an ac wave. The unfiltered output of a wave or a full wave rectifier. In 1820, Hans Christian Orsted discovered that electrical current creates a magnetic field and this discovery made scientists relate magnetism to the electric phenomena. In 1879, Thomas Edison invented the light bulb. He improved a 50-year-old idea using lower current electricity, a vacuum inside the globe and a small carbonized filament. At that time, the idea of lightning was not new. Edison not only invented an incandescent electric light, but an electric lighting system contained all the necessary elements to make the incandescent light safe, economical. Prior to 1879, direct current electricity had been used in lighting for the outdoors and it was in the 1880s when the modern electric utility industry began. It was an evolution from street lighting systems and from gas and it was located in Lower Manhattan, on Pearl Street. This station provided light and electricity to customers in a one square mile range, the station was called Thomas Edisons Pearl Street Electricity Generating Station. This station introduced four elements of an electric utility system, Efficient distribution, competitive price, reliable central generation
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Resistor
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A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses. High-power resistors that can dissipate many watts of power as heat may be used as part of motor controls, in power distribution systems. Fixed resistors have resistances that only slightly with temperature, time or operating voltage. Variable resistors can be used to adjust circuit elements, or as sensing devices for heat, light, humidity, force, Resistors are common elements of electrical networks and electronic circuits and are ubiquitous in electronic equipment. Practical resistors as discrete components can be composed of various compounds, Resistors are also implemented within integrated circuits. The electrical function of a resistor is specified by its resistance, the nominal value of the resistance falls within the manufacturing tolerance, indicated on the component. Two typical schematic diagram symbols are as follows, The notation to state a resistors value in a circuit diagram varies, one common scheme is the letter and digit code for resistance values following IEC60062. It avoids using a separator and replaces the decimal separator with a letter loosely associated with SI prefixes corresponding with the parts resistance. For example, 8K2 as part marking code, in a diagram or in a bill of materials indicates a resistor value of 8.2 kΩ. Additional zeros imply a tighter tolerance, for example 15M0 for three significant digits, when the value can be expressed without the need for a prefix, an R is used instead of the decimal separator. For example, 1R2 indicates 1.2 Ω, and 18R indicates 18 Ω, for example, if a 300 ohm resistor is attached across the terminals of a 12 volt battery, then a current of 12 /300 =0.04 amperes flows through that resistor. Practical resistors also have some inductance and capacitance which affect the relation between voltage and current in alternating current circuits, the ohm is the SI unit of electrical resistance, named after Georg Simon Ohm. An ohm is equivalent to a volt per ampere, since resistors are specified and manufactured over a very large range of values, the derived units of milliohm, kilohm, and megohm are also in common usage. The total resistance of resistors connected in series is the sum of their resistance values. R e q = R1 + R2 + ⋯ + R n, the total resistance of resistors connected in parallel is the reciprocal of the sum of the reciprocals of the individual resistors. 1 R e q =1 R1 +1 R2 + ⋯ +1 R n. For example, a 10 ohm resistor connected in parallel with a 5 ohm resistor, a resistor network that is a combination of parallel and series connections can be broken up into smaller parts that are either one or the other
24.
Three-phase
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In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating current voltages that are offset in time by one-third of the period. A three-phase system may be arranged in delta or star, harmonic current in the neutral may become very large if non-linear loads are connected. Generally, in power systems, the loads are distributed as evenly as is practical between the phases. It is usual practice to discuss a balanced system first and then describe the effects of unbalanced systems as deviations from the elementary case. An important property of three-phase power is that the power available to a resistive load and this is essential for keeping large generators and motors running smoothly. The neutral current is the vector sum of the line currents. In practice, systems rarely have perfectly balanced loads, currents, the analysis of unbalanced cases is greatly simplified by the use of the techniques of symmetrical components. An unbalanced system is analysed as the superposition of three balanced systems, each with the positive, negative or zero sequence of balanced voltages, when specifying wiring sizes in a three-phase system, we only need to know the magnitude of the phase and neutral currents. The neutral current can be determined by adding the three phase currents together as complex numbers and then converting from rectangular to polar co-ordinates, devices that utilize rectifier-capacitor front ends introduce third order harmonics. Third harmonic currents are in-phase on each of the supply phases, any polyphase system, by virtue of the time displacement of the currents in the phases, makes it possible to easily generate a magnetic field that revolves at the line frequency. Such a revolving magnetic field makes polyphase induction motors possible, the field produced by a single-phase winding can provide energy to a motor already rotating, but without auxiliary mechanisms the motor will not accelerate from a stop when energized. A rotating magnetic field of steady amplitude requires that all three phase currents be equal in magnitude, and accurately displaced one-third of a cycle in phase, unbalanced operation results in undesirable effects on motors and generators. Such arrays will evenly balance the load between the phases of the source system. For example, balanced two-phase power can be obtained from a network by using two specially constructed transformers, with taps at 50% and 86. 6% of the primary voltage. This Scott T connection produces a true two-phase system with 90° time difference between the phases, another example is the generation of higher-phase-order systems for large rectifier systems, to produce a smoother DC output and to reduce the harmonic currents in the supply. When three-phase is needed but only single-phase is readily available from the electricity supplier and it is possible to measure the power in a three-phase system using two transducers when there is no neutral, or three transducers when there is neutral. Blondels theorem states that the number of measurement elements required is one less than the number of current-carrying conductors, mcGraw-Hill Electrical and Electronic Engineering Series
25.
Induction motor
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An induction motor can therefore be made without electrical connections to the rotor. An induction motors rotor can be either wound type or squirrel-cage type, three-phase squirrel-cage induction motors are widely used in industrial drives because they are rugged, reliable and economical. Single-phase induction motors are used extensively for smaller loads, such as household appliances like fans, although traditionally used in fixed-speed service, induction motors are increasingly being used with variable-frequency drives in variable-speed service. VFDs offer especially important energy savings opportunities for existing and prospective induction motors in variable-torque centrifugal fan, pump, squirrel cage induction motors are very widely used in both fixed-speed and variable-frequency drive applications. Tesla applied for U. S. patents in October and November 1887 and was granted some of these patents in May 1888, in April 1888, the Royal Academy of Science of Turin published Ferrariss research on his AC polyphase motor detailing the foundations of motor operation. George Westinghouse, who was developing an alternating current power system at time, licensed Tesla’s patents in 1888. Tesla was also employed for one year as a consultant, Westinghouse employee C. F. Scott was assigned to assist Tesla and later took over development of the induction motor at Westinghouse. Steadfast in his promotion of development, Mikhail Dolivo-Dobrovolsky invented the cage-rotor induction motor in 1889. Furthermore, he claimed that Teslas motor was not practical because of two-phase pulsations, G. Lamme developed a rotating bar winding rotor. The General Electric Company began developing three-phase induction motors in 1891, by 1896, General Electric and Westinghouse signed a cross-licensing agreement for the bar-winding-rotor design, later called the squirrel-cage rotor. Arthur E. Kennelly was the first to bring out full significance of the i to designate the 90-degree rotation operator in complex number analysis of AC problems. GEs Charles Proteus Steinmetz greatly developed application of AC complex quantities including in terms now commonly known as the induction motors Steinmetz equivalent circuit. Induction motor improvements flowing from these inventions and innovations were such that a 100-horsepower induction motor currently has the same mounting dimensions as a 7. 5-horsepower motor in 1897. In both induction and synchronous motors, the AC power supplied to the motors stator creates a field that rotates in time with the AC oscillations. Whereas a synchronous motors rotor turns at the rate as the stator field. The induction motor stators magnetic field is changing or rotating relative to the rotor. This induces a current in the induction motors rotor, in effect the motors secondary winding. The rotating magnetic flux induces currents in the windings of the rotor, the currents in the rotor windings in turn create magnetic fields in the rotor that react against the stator field
26.
Torque
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Torque, moment, or moment of force is rotational force. Just as a force is a push or a pull. Loosely speaking, torque is a measure of the force on an object such as a bolt or a flywheel. For example, pushing or pulling the handle of a wrench connected to a nut or bolt produces a torque that loosens or tightens the nut or bolt, the symbol for torque is typically τ, the lowercase Greek letter tau. When it is called moment of force, it is denoted by M. The SI unit for torque is the newton metre, for more on the units of torque, see Units. This article follows US physics terminology in its use of the word torque, in the UK and in US mechanical engineering, this is called moment of force, usually shortened to moment. In US physics and UK physics terminology these terms are interchangeable, unlike in US mechanical engineering, Torque is defined mathematically as the rate of change of angular momentum of an object. The definition of states that one or both of the angular velocity or the moment of inertia of an object are changing. Moment is the term used for the tendency of one or more applied forces to rotate an object about an axis. For example, a force applied to a shaft causing acceleration, such as a drill bit accelerating from rest. By contrast, a force on a beam produces a moment, but since the angular momentum of the beam is not changing. Similarly with any force couple on an object that has no change to its angular momentum and this article follows the US physics terminology by calling all moments by the term torque, whether or not they cause the angular momentum of an object to change. The concept of torque, also called moment or couple, originated with the studies of Archimedes on levers, the term torque was apparently introduced into English scientific literature by James Thomson, the brother of Lord Kelvin, in 1884. A force applied at an angle to a lever multiplied by its distance from the levers fulcrum is its torque. A force of three newtons applied two metres from the fulcrum, for example, exerts the same torque as a force of one newton applied six metres from the fulcrum. More generally, the torque on a particle can be defined as the product, τ = r × F, where r is the particles position vector relative to the fulcrum. Alternatively, τ = r F ⊥, where F⊥ is the amount of force directed perpendicularly to the position of the particle, any force directed parallel to the particles position vector does not produce a torque
27.
MOSFET
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The metal–oxide–semiconductor field-effect transistor is a type of field-effect transistor. It has a gate, whose voltage determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals, although FET is sometimes used when referring to MOSFET devices, other types of field-effect transistors also exist. Because these two terminals are connected to each other internally, only three terminals appear in electrical diagrams. The basic principle of the transistor was first patented by Julius Edgar Lilienfeld in 1925. The main advantage of a MOSFET over a regular transistor is that it very little current to turn on. In enhancement mode MOSFETs, a voltage drop across the oxide induces a conducting channel between the source and drain contacts via the field effect. The term enhancement mode refers to the increase of conductivity with increase in oxide field that adds carriers to the channel, also referred to as the inversion layer. The channel can contain electrons, or holes, opposite in type to the substrate, so nMOS is made with a p-type substrate, the metal in the name MOSFET is now often a misnomer because the previously metal gate material is now often a layer of polysilicon. Aluminium had been the material until the mid-1970s, when polysilicon became dominant. Metallic gates are regaining popularity, since it is difficult to increase the speed of operation of transistors without metal gates, likewise, the oxide in the name can be a misnomer, as different dielectric materials are used with the aim of obtaining strong channels with smaller applied voltages. An insulated-gate field-effect transistor or IGFET is a term almost synonymous with MOSFET. The term may be inclusive, since many MOSFETs use a gate that is not metal. Another synonym is MISFET for metal–insulator–semiconductor FET, the MOSFET is by far the most common transistor in both digital and analog circuits, though the bipolar junction transistor was at one time much more common. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925. Twenty five years later, when Bell Telephone attempted to patent the junction transistor, they found Lilienfeld already holding a patent, Bell Labs was able to work out an agreement with Lilienfeld, who was still alive at that time. It was at time the Bell Labs version was given the name bipolar junction transistor, or simply junction transistor. In 1959, Dawon Kahng and Martin M. Atalla at Bell Labs invented the metal–oxide–semiconductor field-effect transistor as an offshoot to the patented FET design and it used crystalline silicon for the semiconductor and a thermally oxidized layer of silicon dioxide for the insulator
28.
Transistor
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A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit, a voltage or current applied to one pair of the transistors terminals controls the current through another pair of terminals. Because the controlled power can be higher than the controlling power, today, some transistors are packaged individually, but many more are found embedded in integrated circuits. The transistor is the building block of modern electronic devices. Julius Edgar Lilienfeld patented a field-effect transistor in 1926 but it was not possible to construct a working device at that time. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, the thermionic triode, a vacuum tube invented in 1907, enabled amplified radio technology and long-distance telephony. The triode, however, was a device that consumed a substantial amount of power. Physicist Julius Edgar Lilienfeld filed a patent for a transistor in Canada in 1925. Lilienfeld also filed patents in the United States in 1926 and 1928. However, Lilienfeld did not publish any research articles about his devices nor did his patents cite any examples of a working prototype. In 1934, German inventor Oskar Heil patented a device in Europe. Solid State Physics Group leader William Shockley saw the potential in this, the term transistor was coined by John R. Pierce as a contraction of the term transresistance. Instead, what Bardeen, Brattain, and Shockley invented in 1947 was the first point-contact transistor, Mataré had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II. Using this knowledge, he began researching the phenomenon of interference in 1947, realizing that Bell Labs scientists had already invented the transistor before them, the company rushed to get its transistron into production for amplified use in Frances telephone network. The first bipolar junction transistors were invented by Bell labs William Shockley, on April 12,1950, Bell Labs chemists Gordon Teal and Morgan Sparks had successfully produced a working bipolar NPN junction amplifying germanium transistor. Bell Labs had made this new sandwich transistor discovery announcement, in a release on July 4,1951. The first high-frequency transistor was the surface-barrier germanium transistor developed by Philco in 1953 and these were made by etching depressions into an N-type germanium base from both sides with jets of Indium sulfate until it was a few ten-thousandths of an inch thick
29.
Voltage
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Voltage, electric potential difference, electric pressure or electric tension is the difference in electric potential energy between two points per unit electric charge. The voltage between two points is equal to the work done per unit of charge against an electric field to move the test charge between two points. This is measured in units of volts, voltage can be caused by static electric fields, by electric current through a magnetic field, by time-varying magnetic fields, or some combination of these three. A voltmeter can be used to measure the voltage between two points in a system, often a reference potential such as the ground of the system is used as one of the points. A voltage may represent either a source of energy or lost, used, given two points in space, x A and x B, voltage is the difference in electric potential between those two points. Electric potential must be distinguished from electric energy by noting that the potential is a per-unit-charge quantity. Like mechanical potential energy, the zero of electric potential can be chosen at any point, so the difference in potential, i. e. the voltage, is the quantity which is physically meaningful. The voltage between point A to point B is equal to the work which would have to be done, per unit charge, against or by the electric field to move the charge from A to B. The voltage between the two ends of a path is the energy required to move a small electric charge along that path. Mathematically this is expressed as the integral of the electric field. In the general case, both an electric field and a dynamic electromagnetic field must be included in determining the voltage between two points. Historically this quantity has also called tension and pressure. Pressure is now obsolete but tension is used, for example within the phrase high tension which is commonly used in thermionic valve based electronics. Voltage is defined so that negatively charged objects are pulled towards higher voltages, therefore, the conventional current in a wire or resistor always flows from higher voltage to lower voltage. Current can flow from lower voltage to higher voltage, but only when a source of energy is present to push it against the electric field. This is the case within any electric power source, for example, inside a battery, chemical reactions provide the energy needed for ion current to flow from the negative to the positive terminal. The electric field is not the only factor determining charge flow in a material, the electric potential of a material is not even a well defined quantity, since it varies on the subatomic scale. A more convenient definition of voltage can be found instead in the concept of Fermi level, in this case the voltage between two bodies is the thermodynamic work required to move a unit of charge between them
30.
Ampere
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The ampere, often shortened to amp, is a unit of electric current. In the International System of Units the ampere is one of the seven SI base units and it is named after André-Marie Ampère, French mathematician and physicist, considered the father of electrodynamics. SI defines the ampere in terms of base units by measuring the electromagnetic force between electrical conductors carrying electric current. The ampere was then defined as one coulomb of charge per second, in SI, the unit of charge, the coulomb, is defined as the charge carried by one ampere during one second. In the future, the SI definition may shift back to charge as the base unit, ampères force law states that there is an attractive or repulsive force between two parallel wires carrying an electric current. This force is used in the definition of the ampere. The SI unit of charge, the coulomb, is the quantity of electricity carried in 1 second by a current of 1 ampere, conversely, a current of one ampere is one coulomb of charge going past a given point per second,1 A =1 C s. In general, charge Q is determined by steady current I flowing for a time t as Q = It, constant, instantaneous and average current are expressed in amperes and the charge accumulated, or passed through a circuit over a period of time is expressed in coulombs. The relation of the ampere to the coulomb is the same as that of the watt to the joule, the ampere was originally defined as one tenth of the unit of electric current in the centimetre–gram–second system of units. That unit, now known as the abampere, was defined as the amount of current that generates a force of two dynes per centimetre of length between two wires one centimetre apart. The size of the unit was chosen so that the derived from it in the MKSA system would be conveniently sized. The international ampere was a realization of the ampere, defined as the current that would deposit 0.001118 grams of silver per second from a silver nitrate solution. Later, more accurate measurements revealed that this current is 0.99985 A, at present, techniques to establish the realization of an ampere have a relative uncertainty of approximately a few parts in 107, and involve realizations of the watt, the ohm and the volt. Rather than a definition in terms of the force between two current-carrying wires, it has proposed that the ampere should be defined in terms of the rate of flow of elementary charges. Since a coulomb is equal to 6. 2415093×1018 elementary charges. The proposed change would define 1 A as being the current in the direction of flow of a number of elementary charges per second. In 2005, the International Committee for Weights and Measures agreed to study the proposed change, the new definition was discussed at the 25th General Conference on Weights and Measures in 2014 but for the time being was not adopted. The current drawn by typical constant-voltage energy distribution systems is usually dictated by the power consumed by the system, for this reason the examples given below are grouped by voltage level
31.
Moquette
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Moquette, derived from the French word for carpet, is a type of woven pile fabric in which cut or uncut threads form a short dense cut or loop pile. As well as giving it a distinctive velvet-like feel, the construction is particularly durable. Its upright fibres form a flexible, non-rigid surface, which are displaced to give durability. Traditional moquette fabrics are made from a wool nylon face with a cotton backing. Moquette originated in France, where it was woven by hand, the standard width was a Flemish ell of 27 inches. There were two finishes, moquette velouté, which had a cut pile like English Wilton, and moquette bouclé and it is still woven in Yorkshire using traditional techniques. A long-standing moquette manufacturer is Holdsworth Fabrics which dates back to 1822, the most famous moquette in the United States is the one sent by Louis XVI to George Washington. It was made for the room in Mount Vernon, where it can be seen today. Moquette is famous for being used on London Transports vehicles, particularly the seats of London Undergrounds Tube trains, during the decades of the many railway companies, there were some ten moquette manufacturers in the UK. As a result of the nationalisation of the railways after World War II and then the Beeching cuts of the early 1960s, by the mid 1960s there were two suppliers, one of which was Courtaulds. The other is Holdsworth Fabrics based in Huddersfield, UK, moquette is occasionally used in clothing. In 1932-33, the United States Army Air Corps contracted for cold-weather leather flight suits lined with moquette, apparently as an economy substitute for sheepskin
32.
London Underground 1996 Stock
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The London Underground 1996 stock is a type of rolling stock used on the Jubilee line of the London Underground. It was built by GEC Alsthom-Metro Cammell and began service in 1997 and its sister stock is the 1995 Stock used on the Northern line, having been built at a similar time by the same manufacturer. The original 59 trains were operated in a 6-car formation. At the same time, four additional 7-car trains were ordered, detailed design was done by Alstom S. A. at its Birmingham and Rugby facilities, and the first six train sets were manufactured in Alstoms Barcelona factory to the 1996 stock design. All type approvals were conducted on these early train sets,1995 stock was produced in the Barcelona factory afterwards, and the balance of the 1996 stock followed. Final assembly and equipping was at Alstoms facility at Washwood Heath, Birmingham,1995 and 1996 stock are similar but have different interiors, seating layouts and cabs, traction packages and train management systems, and slight differences in tripcock geometry. 1995 stock uses LED body-side lights,1996 stock filament bulbs, Alstom subsequently won the maintenance contract for 1996 stock, to be carried out at the new Stratford market depot in East London. The stock was bought for the opening of the Jubilee Line Extension from Green Park to Stratford, the original plan was to refurbish 1983 stock with the same exterior and interior as 1996 stock, even with double doors, but it proved too expensive. However, the opening of the JLE was delayed, and the 1996 stock replaced 1983 stock between Christmas Eve 1997 and July 1998, over a year before the JLE opened. They were removed during the car project, only train numbers 96066 to 96466 and 96012 to 96412 still retain them. The stock was delivered as six-car trains, with two units coupled together, each consisting of a Driving Motor car, a Trailer car. The standard train formation was DM–T–UNDM+UNDM–T–DM, twelve later trailer cars had de-icing equipment, these are referred to as De-Icing Trailer cars. The cars are odd-numbered at one end of the train, even numbers at the other. Each number has five digits, the first two are the type, the third refers to the car type,0 or 1 for DM,2 or 3 for T,4 or 5 for UNDM and 8 or 9 for DIT. Thus, for example, a train set would be 96001,96201,96401,96402,96202,96002. Each car is given a letter designation, the even cab car is A, odd cab car B, even UNDM C, odd UNDM D, trailer cars E, DIT F. In early 2005 London Underground announced that it would add a car to each train. The original factory on the Barcelona sea front had been closed, the four new trains were built as six-car trains and modified to seven-car configuration at Stratford Depot
33.
London Underground 1973 Stock
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The London Underground 1973 Stock is a type of rolling stock used on the Piccadilly line of the London Underground. It was introduced into service in 1975 with the extension of the line to Hatton Cross in 1975, the trains were built by Metro Cammell between 1974 and 1977, and were refurbished by Bombardier Transportation between 1995 and 2000. In the early 1970s London Transport placed an order of 88 trains to replace the 1959 stock, built between 1972 and 1975 by Metro Cammell in Birmingham, the first unit entered service on 19 July 1975 and the last was introduced by 1977. The trains featured longer cars and larger space than the previous ones. The stock was refurbished by Bombardier Transportation between 1996 and 2001, changes included the removal of transverse seating, strap hangers replaced with grab bars, new floor material, and a full repaint into London Undergrounds corporate livery. The peak Piccadilly line service requires 79 trains in operation, each train is made up of two units of three cars. The trains are maintained in Cockfosters and Northfields depots, like all London Underground trains, the stock operate on a four-rail 630V DC power system. In November 2006, the system was reintroduced with another automated announcer featuring the voice of Julie Berry, the driver can select between two settings, commuter and tourist. Certain stations include announcements warning of the gap between the train and platform, interchanges with other London Underground lines and other rail services are also included in announcements, such as Kings Cross St Pancras which includes St Pancras International. The EVO tube concept design, an articulated train with walk through cars, was introduced early in 2011. The proposal introduces fully automated trains and signalling to increase capacity first on the Piccadilly line in 2025, followed the Central, Waterloo & City, and Bakerloo lines by 2033. The fully automated trains may not have drivers, however the ASLEF and RMT trade unions that represent the drivers strongly oppose this, saying it would be unsafe
34.
National Rail
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The name and the accompanying double arrow symbol are the intellectual property of the Secretary of State for Transport. The National Rail logo was introduced by ATOC in 1999, and was used on the Great Britain public timetable for the first time in the edition valid from 26 September in that year. Rules for its use are set out in the Corporate Identity Style Guidelines published by the Rail Delivery Group, the NR title is sometimes described as a brand. As it was used by British Rail, the operator before franchising, its use also maintains continuity and public familiarity. National Rail should not be confused with Network Rail, the two networks are generally coincident where passenger services are run. Most major Network Rail lines carry traffic and some lines are freight only. About twenty privately owned operating companies, each franchised for a defined term by government. The Rail Delivery Group is the association representing the TOCs and provides core services. It also runs Rail Settlement Plan, which allocates ticket revenue to the various TOCs, and Rail Staff Travel and it does not compile the national timetable, which is the joint responsibility of the Office of Rail Regulation and Network Rail. Since the privatisation of British Rail there is no longer a single approach to design on railways in Great Britain, the look and feel of signage, liveries and marketing material is largely the preserve of the individual TOCs. However, National Rail continues to use BRs famous double-arrow symbol and it has been incorporated in the National Rail logotype and is displayed on tickets, the National Rail website and other publicity. The trademark rights to the arrow symbol remain state-owned, being vested in the Secretary of State for Transport. The double arrow was already prescribed for indicating a railway station, the lettering used in the National Rail logotype is a modified form of the typeface Sassoon Bold. It is a misconception that Rail Alphabet was also used for printed material. The British Rail typefaces of choice from 1965 were Helvetica and Univers, TOCs may use what they like, examples include Futura, Helvetica, Frutiger, Bliss, and a modified version of Precious by London Midland. Several conurbations have their own metro or tram systems, most of which are not part of National Rail, LO now also possesses some infrastructure in its own right, following the reopening of the former East London line of London Underground as the East London Railway of LO. Heathrow Express and Eurostar are also not part of the National Rail network despite sharing of stations, northern Ireland Railways were never part of British Rail, which was always confined to Great Britain, and therefore are not part of the National Rail network. National Rail services have a common ticketing structure inherited from British Rail, through tickets are available between any pair of stations on the network, and can be bought from any station ticket office
35.
Tube Lines
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The company has been a wholly owned subsidiary of Transport for London since May 2010 and has now been rebranded as London Underground. However, the Tube Lines logo remain widely visible on staff uniforms, Tube Lines headquarters are at 15 Westferry Circus, London. Tube Lines was established under a Public-Private Partnership scheme in 2003 to provide services to the London Underground, together with another company. Metronet entered administration in 2008 and was bought by TfL, Tube Lines was also bought by TfL in 2010 following a funding shortfall. The company was founded by a consortium of Amey plc, Bechtel, in 2005, Jarvis sold its stake to fellow shareholder Amey for £147 million. The remaining lines of the London Underground were part of Metronet, which existed from 2003 to 2008, combined with the takeover of Metronet, this means that all maintenance is now managed in-house, despite TfL using a large number of private suppliers and contractors
36.
Golders Green
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Golders Green is an area in the London Borough of Barnet in England. Although the settlement history goes back to the 18th century, Golders Green is essentially a late 19th-century suburban development and it is situated approximately 5.5 miles north west of Charing Cross and centred on the intersection of Golders Green Road and Finchley Road. It was historically part of Middlesex, and formed part of the Municipal Borough of Hendon until 1965, the area has a wide variety of housing and a busy main shopping street, Golders Green Road. It is known for its large Jewish population as well as for being home to the largest Jewish kosher hub in the United Kingdom, which attracts many Jewish tourists. The name Golders comes from a family named Godyere who lived in the area, Golders Green has been a place in the parish and manor of Hendon since around the 13th century. The earliest references to the name of the adjacent district of Temple Fortune is on a map, however this name reveals a much earlier history. It is likely that the name refers to the Knights of St John, Fortune may be derived from a small settlement on the route from Hampstead to Hendon. Here a lane from Finchley, called Ducksetters Lane, intersected and it is likely that the settlement was originally the Bleccanham estate. By the end of the 18th century Temple Fortune Farm was established on the side of Farm Close. The building of Finchley Road replaced Ducksetters Lane as a route to Finchley, Hendon Park Row is of this period, and consisted of around thirty small dwellings built by a George Stevens, which were, with two exceptions, demolished around 1956. A small dame school and prayer house run by Anglican deaconesses existed in the 1890s and 1900s, along Finchley Road were a number of villas, joined by the Royal Oak public house. By the end of the 19th century there were around 300 people living in the area, which included a laundry, the principal industry was brick making. In 1895 a Jewish cemetery was established adjacent to Hoop Lane, Golders Green Crematorium was opened in 1902. A significant moment in Temple Fortunes development into a suburban area occurred in 1907, the establishment of Hampstead Garden Suburb brought major changes to the area east of Finchley Road. Temple Fortune Farm was demolished and along the front of the road the building of the Arcade, both the Golders Green Hippodrome, former home of the BBC Concert Orchestra, and the police station opened in 1913. The now-demolished Orpheum Theatre was intended to rival the Hippodrome in Golders Green, the remainder of the Golders Green area is covered by the Childs Hill and Garden Suburb electoral wards. The same boundaries are used for the Golders Green, Childs Hill, the area is adjacent to the Heath Extensions part of Hampstead Heath. Ethnically, the Golders Green ward was 64% white, indians, Other Asians and Black Africans made up 5% each
37.
Golders Green tube station
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Golders Green is a London Underground station in Golders Green, north London. The station is on the Edgware branch of the Northern line between Hampstead and Brent Cross and it is in Travelcard zone 3 and is the first surface station on the Edgware branch when heading north. The station is located at the crossroads of Finchley Road and Golders Green Road/North End Road, the station exit is adjacent to Golders Green bus station, a former exit to Finchley Road is now closed. Adjacent to the station is the Golders Green Hippodrome, home to the BBC Concert Orchestra for many years, Golders Green station was opened by the Charing Cross, Euston & Hampstead Railway on 22 June 1907. It was one of the two northern terminals and was also the site of the railways depot. To the south of the station in the tunnels beneath Hampstead Heath is the partially built, the war postponed the construction of the extension and work did not begin until 12 June 1922. The first section of the extension, as far as Hendon Central, Golders Green was the last station on the Northern line to retain semaphore signals, replaced in 1950. The Golders Green station has three tracks running through it which serve a platform and two island platforms. The platforms are numbered 1 to 5 with numbers 1 and 2 serving each side of one track and 3 and 4 serving each side of another, platform 1 is not presently in public use. Two new lifts were installed during 2008, one on platform 2/3, the maintenance of the station now falls under Tube Lines as part of the Public-Private Partnership
38.
Morden
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Morden is a district in the London Borough of Merton. It is located approximately 8 miles South-southwest of central London between Merton Park and Wimbledon, Mitcham, Sutton and Worcester Park, Morden had a population of 48,233 in 2011. Morden might get its name either from the British language words Mawr and Dun, small Roman artifacts, mainly coins and pottery, have been found at various locations within the area although there is no evidence of any settlement. In 1086, the Domesday Book recorded the manor as Mordone and it was held by Westminster Abbey and its assets were,3 hides,1 mill worth £2 and 7 ploughs. Fourteen people were recorded as living in the area, the manor and village remained abbey property until the Dissolution of the Monasteries in Henry VIIIs reign when the manor was sold to Lionel Ducket and Edward Whitchurch. Together, they sold it on the year to Sir Richard Garth who became Lord of the Manor. The Garth family owned the land and maintained their connection with the parish for the four centuries. The prominence of the Garth family is recorded locally in the name of Garth Road, Lower Morden, the two lions included in the present civic arms of the London Borough of Merton are adopted from the arms of Sir Richard. While the population of Wimbledon grew hugely from 1,591 in 1801 to 41,652 in 1901, the population of Morden was 512 in 1801 and, one hundred years later, had grown to just 960. In 1871, the area of the parish of Morden was 1,474.926 acres with the village clustered around St Lawrence’s church at the top of the hill on the road from London to Epsom. Approximately half a mile to the west of the main village, close to the church were the George Inn, a 17th-century coaching inn, the estate of Morden Park and a school. The other main public house in the village was the Crown Inn, the rest of what is now the commercial centre of Morden was fields. By 1898, the works had gone and there was a brickworks on the site of Mostyn Gardens in Martin Way. Under the Local Government Act,1894, the parish of Morden formed part of the Croydon Rural District of Surrey, Morden was merged with the Merton Urban District, in 1913, to form the Merton and Morden Urban District. Away from the new centre of Morden, the existing rural roads were widened and rebuilt. Further transport improvements came with the construction of a new Southern Railway branch line from Wimbledon to Sutton via stations at South Merton, the new line opened in January 1930. As a result of the new links, the population of Morden increased rapidly from 1,355 in 1921 to 12,618 in 1931. In the next fifteen years, the continued to grow
39.
High Barnet tube station
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High Barnet is a London Underground station, and former railway station, located in Chipping Barnet in North London. The station is the terminus of the High Barnet branch of the Northern line and is in Travelcard Zone 5 and it is the northernmost station on the Northern line and is situated 10.2 miles north north-west of Charing Cross. The next station south is Totteridge & Whetstone, when trains are no longer required to run on the Northern line, they may be stabled on the sidings to the east of the station. High Barnet station was planned by the Edgware, Highgate and London Railway and was opened on 1 April 1872 by the Great Northern Railway on the original site of the Barnet Faire. It was the terminus of the branch of a line ran from Finsbury Park to Edgware via Highgate. After the 1921 Railways Act created the Big Four railway companies the line was, from 1923, the section of the High Barnet branch north of East Finchley was incorporated into the London Underground network through the Northern Heights project begun in the late 1930s. High Barnet station was first served by Northern line trains on 14 April 1940 and, the station still retains much of its original Victorian architectural character today, a considerable number of platform buildings dating from the pre-LT era. In the Autumn 2008, a new train crew accommodation block began construction immediately to the south west of the station in part of the car park. This accommodation was opened on 31 January 2010, there are also two accessible toilets now available. These works were completed in October 2009. Many London Buses Routes serve the station on nearby roads near High Barnet Station and this is due to the position of High Barnet Station in the surrounding steep geography of Barnet Hill
40.
Highgate tube station
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Highgate is a London Underground station and former railway station in Archway Road, in the London Borough of Haringey in north London. The station takes its name from nearby Highgate Village and it is on the High Barnet branch of the Northern line, between Archway and East Finchley stations and is in Travelcard Zone 3. The station was opened in 1867 as part of the Great Northern Railways line between Finsbury Park and Edgware stations. As part of their only partially completed Northern Heights plan, the London Underground started serving the station in 1941, the platforms of the surface station remain, but were last used in 1954, and the section of the line through them to Finsbury Park was lifted by 1972. One of the original 1867 station buildings still exists, and is in use as a private house, Highgate station was originally constructed by the Edgware, Highgate and London Railway in the 1860s on its line from Finsbury Park station to Edgware station. Before the line was opened it was purchased in July 1867 by the larger Great Northern Railway, whose line from Kings Cross ran through Finsbury Park on its way to Potters Bar. The station opened along with the railway to Edgware on 22 August 1867, because of the hilly terrain, the station was built in a deep cutting excavated from Highgate Hill adjacent to Archway Road. Tunnels penetrated the hillside at each end of the station, leading towards East Finchley to the north, when built, the station had two side platforms, with three tracks between them, and a station building on the south side. A footbridge linked the two platforms, a branch line was constructed from Highgate to Alexandra Palace by the Muswell Hill Railway and opened on 22 May 1872. The new branch split from the route north of the station in a wide arc around Highgate Wood. The next station on the line when it opened was Muswell Hill. In the 1880s, the station was rebuilt, with two flanking a central island platform instead of the two side platforms. The island platform was accessed from an office in the middle of the footbridge. In 1911, the MHR branch was taken over by the GNR, after the 1921 Railways Act created the Big Four railway companies, the GNR became part of the London & North Eastern Railway in 1923. To provide an interchange between the new platforms and the existing surface platforms, a subterranean concourse was constructed immediately beneath the existing station. The concourse was connected to the platforms with escalators and to the existing platforms by stairs. Street entrances to the concourse were provided from the south and the north, at the same time, the buildings on the surface platforms were partly reconstructed and the footbridge was removed. Northern line services through the new tunnels to East Finchley started operating on 3 July 1939 although they did not stop at Highgate until later, following the outbreak of the Second World War in September 1939, works to complete the electrification of the LNER lines were slowed or halted
41.
Kennington tube station
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Kennington is a London Underground station on Kennington Park Road in Kennington on both the Charing Cross and Bank branches of the Northern line. It is within the London Borough of Southwark and its neighbouring stations to the north are Waterloo on the Charing Cross branch and Elephant & Castle on the Bank branch, the next station to the south is Oval. The station is in Travelcard Zone 2, the station was opened on 18 December 1890 as part of Londons first deep-level tube, the City & South London Railway. The layout was similar to the current arrangement at Borough, with one platform having level access to the lift. Two extra platforms were added in 1926, when the connection via Waterloo to Embankment on the former Charing Cross, Euston & Hampstead Railway was built. Therefore, to ease the burden on passengers, the landing was raised up, by one floor, to the bridge level. It is therefore the station of the C&SLRs original section still in a condition close to its original design. The station reopened after its first extensive refurbishment in more than eighty years, the station has two passenger lifts but no escalators. The platforms can also be reached via the 79-step staircase, refurbishment work at Kennington was completed in 2005. The 20 A1-sized panels inside the two lifts, normally used for posters, were occupied in 2010 by the work of the 16 MA students at the City & Guilds of London Art School. Since 2005 Art Below have set about changing the everyday travelling experience, transforming entire platforms and this was the first time that they had transformed a lift into an art gallery. During peak times, northbound trains are scheduled to terminate at Mill Hill East. An average time taken for a Northern line train to travel between Waterloo and Kennington is approximately 3 minutes and 50 seconds, London Bus routes 133,155,333 and 415 and night routes N133 and N155 serve the station. Because of the arrangement of junctions, trains using the loop cannot reach the northbound Bank branch platform nor can trains from the southbound Bank branch reach the loop. For southbound Charing Cross branch or Bank branch trains to reach the northbound Bank branch platform a reversing siding between the two running tunnels must be used, because of the layout, it is almost always southbound Charing Cross branch trains that terminate at Kennington. One of the four platforms is thus mainly used by terminating trains. London Transport Museum Photographic Archive Station in original condition,1916 Station after 1920s changes 3D drawing of the current layout of Kennington Station, and loop
42.
Euston tube station
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Euston is a London Underground station served by the Victoria line and both branches of the Northern line. It directly connects with Euston main line station above it, the station is in Travelcard Zone 1. Euston was constructed as two separate underground stations, three of the four Northern line platforms date from the stations opening in 1907. The fourth Northern line platform and the two Victoria line platforms were constructed in the 1960s when the station was altered to accommodate the Victoria line. Plans for High Speed 2 and Crossrail 2 both include proposals to modify the station to provide interchanges with the new services, on the Northern lines Bank branch the station is between Camden Town and Kings Cross St Pancras. On the Charing Cross branch it is between Mornington Crescent and Warren Street, on the Victoria line it is between Warren Street and Kings Cross St. Pancras. The station is near Euston Square station allowing connections at street level to the Circle, Hammersmith & City, an underground station to serve Euston station was first proposed by the Hampstead, St Pancras & Charing Cross Railway in 1891. For the remainder of the 1890s, the CCE&HR struggled unsuccessfully to raise the capital it needed to fund the construction, whilst it did so it continued to develop its route proposals. In 1899, parliamentary permission was obtained to modify the route so that the Euston branch was extended northwards to connect to the route at the south end of Camden High Street. The section of the route between the two ends of the loop was omitted. In 1900, the CCE&HR was taken over by a led by American financier Charles Yerkes which raised the necessary money. Also in 1900, a proposal was presented to parliament by the Islington and Euston Railway for an extension of the City, at the time, the C&SLR was in the process of constructing an extension to Angel from its recently opened terminus at Moorgate Street. The extension plan was initially permitted in 1901, but delays in the process meant that it had to be re-submitted the following year. The second submission was opposed by the Metropolitan Railway, which saw the extension as competition to its service between Kings Cross and Moorgate, and the plan was rejected. A third attempt, presented to parliament in November 1902 by the C&SLR itself, was successful, with funding obtained, tunnelling for the CCE&HR was carried out between September 1903 and December 1905, after which the station buildings and fitting-out of the tunnels commenced. The CCE&HR opened on 22 June 1907, its building, designed by Leslie Green, is located at the corner of Drummond Street, another passage led to lifts that surfaced within the main line station itself. The CCE&HR building remains, but the C&SLRs building was demolished in 1934 to enable the construction of Euston House for the London, Midland, the smaller tunnel size restricted the capacity of the C&SLRs trains and, in 1912, the C&SLR published a bill for their enlargement. A separate bill was published at the time by the London Electric Railway
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Seating capacity
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Seating capacity is the number of people who can be seated in a specific space, in terms of both the physical space available, and limitations set by law. Seating capacity can be used in the description of anything ranging from an automobile that seats two to a stadium that seats hundreds of thousands of people. The International Fire Code, portions of which have adopted by many jurisdictions, is directed more towards the use of a facility than the construction. It specifies, For areas having fixed seating without dividing arms and it also requires that every public venue submit a detailed site plan to the local fire code official, including details of the means of egress, seating capacity, arrangement of the seating. Once safety considerations have been satisfied, determinations of seating capacity turn on the size of the venue. For sports venues, the decision on maximum seating capacity is determined by several factors, chief among these are the primary sports program and the size of the market area. Seating capacity of venues also plays a role in what media they are able to provide, in contracting to permit performers to use a theatre or other performing space, the seating capacity of the performance facility must be disclosed. Seating capacity may influence the kind of contract to be used, the seating capacity must also be disclosed to the copyright owner in seeking a license for the copyrighted work to be performed in that venue. Venues that may be leased for private functions such as ballrooms and auditoriums generally advertise their seating capacity, seating capacity is also an important consideration in the construction and use of sports venues such as stadiums and arenas. The seating capacity for restaurants is reported as covers, a restaurant that can seat 99 is said to have 99 covers, seating capacity differs from total capacity, which describes the total number of people who can fit in a venue or in a vehicle either sitting or standing. Use of the term public capacity indicates that a venue is allowed to more people than it can actually seat. Again, the total number of people can refer to either the physical space available or limitations set by law
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Folding seat
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A Folding seat is a seat that folds away so as to occupy less space. When installed on a transit bus it makes room for a wheelchair or two, when installed on a passenger car, it provides extra seating. In churches it may have a projection called a misericord, which offers support to a person standing in front when the seat is folded. Folding seats may also be found in stadiums, arenas, theaters and auditoriums where they facilitate entry, some folding seats in rapid transit may fold down rather than fold up. Flexible seatsdead link] Folding locomotive seat Folding seat Folding boat seat Folding seats
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International Standard Book Number
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The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later. Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0. For example, the edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces. Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations. Australia, ISBNs are issued by the library services agency Thorpe-Bowker
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Totteridge & Whetstone tube station
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Totteridge & Whetstone is a London Underground station in Whetstone of the London Borough of Barnet, North London. The station is the one on the High Barnet branch of the Northern line. The station is on the side of Totteridge Lane, somewhat to the east of the Dollis Brook hence is in Whetstone. The Totteridge & Whetstone station was planned by the Edgware, Highgate and London Railway and was opened as Whetstone. The station was on a line that ran from Finsbury Park to Edgware via Highgate. After the 1921 Railways Act created the Big Four railway companies the line was, from 1923, part of the London and North Eastern Railway. The section of the High Barnet branch north of East Finchley was incorporated into the London Underground network through the Northern Heights project which begun in the late 1930s. Totteridge and Whetstone station was first served by Northern line trains on 14 April 1940 and, the station still retains much of its original Victorian architectural character today. The station is not wheelchair accessible owing to flights of stairs to both the northbound and southbound platforms, the station has ticket halls, three gates, toilets, payphones, a car park, waiting room and two snack vending machines. The ticket office opens on Mondays to Saturdays only, train frequencies vary throughout the day, but generally operate every 3–6 minutes between 6,04 and midnight in both directions. London Bus routes 34,125,234,251,263,326,383,605,626,628,634 and 688 and night route N20 serve the station
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