An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. It consists of one or more conductors (commonly multiples of three) suspended by towers or poles. Since most of the insulation is provided by air, overhead power lines are generally the lowest-cost method of power transmission for large quantities of electric energy.

Construction

Towers for support of the lines are made of wood (as-grown or laminated), steel or aluminum (either lattice structures or tubular poles), concrete, and occasionally reinforced plastics.  The bare wire conductors on the line are generally made of aluminum (either plain or reinforced with steel, or composite materials such as carbon and glass fiber), though some copper wires are used in medium-voltage distribution and low-voltage connections to customer premises. A major goal of overhead power line design is to maintain adequate clearance between energized conductors and the ground so as to prevent dangerous contact with the line, and to provide reliable support for the conductors, resilience to storms, ice loads, earthquakes and other potential damage causes.
Today overhead lines are routinely operated at voltages exceeding 765,000 volts between conductors, with even higher voltages possible in some cases.

Classification by operating voltage

Overhead power transmission lines are classified in the electrical power industry by the range of voltages:
 Low voltage (LV) – less than 1000 volts, used for connection between a residential or small commercial customer and the utility.
 Medium voltage (MV; distribution) – between 1000 volts (1 kV) and 69 kV, used for distribution in urban and rural areas.
 High voltage (HV; subtransmission less than 100 kV; subtransmission or transmission at voltages such as 115 kV and 138 kV), used for sub-transmission and transmission of bulk quantities of electric power and connection to very large consumers.
 Extra high voltage (EHV; transmission) – from 345 kV, up to about 800 kV, used for long distance, very high power transmission.
 Ultra high voltage (UHV) – higher than 800 kV. The Financial Times reported UHV lines are a "game changer", making a global electricity grid potentially feasible.  StateGrid said that compared to conventional lines, UHV enables the transmission of five times more power, over six times the distance.

Structures

Structures for overhead lines take a variety of shapes depending on the type of line. Structures may be as simple as wood poles directly set in the earth, carrying one or more cross-arm beams to support conductors, or "armless" construction with conductors supported on insulators attached to the side of the pole.  Tubular steel poles are typically used in urban areas.  High-voltage lines are often carried on lattice-type steel towers or pylons. For remote areas, aluminum towers may be placed by helicopters. Concrete poles have also been used. Poles made of reinforced plastics are also available, but their high cost restricts application.

Each structure must be designed for the loads imposed on it by the conductors. The weight of the conductor must be supported, as well as dynamic loads due to wind and ice accumulation, and effects of vibration. Where conductors are in a straight line, towers need only resist the weight since the tension in the conductors approximately balances with no resultant force on the structure.  Flexible conductors supported at their ends approximate the form of a catenary, and much of the analysis for construction of transmission lines relies on the properties of this form.

A large transmission line project may have several types of towers, with "tangent" ("suspension" or "line" towers, UK) towers intended for most positions and more heavily constructed towers used for turning the line through an angle, dead-ending (terminating) a line, or for important river or road crossings.  Depending on the design criteria for a particular line, semi-flexible type structures may rely on the weight of the conductors to be balanced on both sides of each tower.  More rigid structures may be intended to remain standing even if one or more conductors is broken.  Such structures may be installed at intervals in power lines to limit the scale of cascading tower failures.

Foundations for tower structures may be large and costly, particularly if the ground conditions are poor, such as in wetlands.  Each structure may be stabilized considerably by the use of guy wires to counteract some of the forces applied by the conductors.

Power lines and supporting structures can be a form of visual pollution. In some cases the lines are buried to avoid this, but this "undergrounding" is more expensive and therefore not common.

For a single wood utility pole structure, a pole is placed in the ground, then three crossarms extend from this, either staggered or all to one side. The insulators are attached to the crossarms. For an "H"-type wood pole structure, two poles are placed in the ground, then a crossbar is placed on top of these, extending to both sides. The insulators are attached at the ends and in the middle. Lattice tower structures have two common forms. One has a pyramidal base, then a vertical section, where three crossarms extend out, typically staggered. The strain insulators are attached to the crossarms. Another has a pyramidal base, which extends to four support points. On top of this a horizontal truss-like structure is placed.

A grounded wire is sometimes strung along the tops of the towers to provide lightning protection. An optical ground wire is a more advanced version with embedded optical fibers for communication. Overhead wire markers can be mounted on the ground wire to meet International Civil Aviation Organization recommendations.
Some markers include flashing lamps for night-time warning.

Circuits
A single-circuit transmission line carries conductors for only one circuit. For a three-phase system, this implies that each tower supports three conductors.

A double-circuit transmission line  has two circuits. For three-phase systems, each tower supports and insulates six conductors. Single phase AC-power lines as used for traction current have four conductors for two circuits. Usually both circuits operate at the same voltage.

In HVDC systems typically two conductors are carried per line, but in rare cases only one pole of the system is carried on a set of towers.

In some countries like Germany most power lines with voltages above 100 kV are implemented as double, quadruple or in rare cases even hextuple power line as rights of way are rare. Sometimes all conductors are installed with the erection of the pylons; often some circuits are installed later. A disadvantage of double circuit transmission lines is that maintenance can be difficult, as either work in close proximity of high voltage or switch-off of two circuits is required.  In case of failure, both systems can be affected.

The largest double-circuit transmission line is the Kita-Iwaki Powerline.

Insulators

Insulators must support the conductors and withstand both the normal operating voltage and surges due to switching and lightning.  Insulators are broadly classified as either pin-type,  which support the conductor above the structure, or suspension type, where the conductor hangs below the structure. The invention of the strain insulator was a critical factor in allowing higher voltages to be used.

At the end of the 19th century, the limited electrical strength of telegraph-style pin insulators limited the voltage to no more than 69,000 volts. Up to about 33 kV (69 kV in North America) both types are commonly used. At higher voltages only suspension-type insulators are common for overhead conductors.

Insulators are usually made of wet-process porcelain or toughened glass, with increasing use of glass-reinforced polymer insulators. However, with rising voltage levels, polymer insulators (silicone rubber based) are seeing increasing usage. China has already developed polymer insulators having a highest system voltage of 1100 kV and India is currently developing a 1200 kV (highest system voltage) line which will initially be charged with 400 kV to be upgraded to a 1200 kV line.

Suspension insulators are made of multiple units, with the number of unit insulator disks increasing at higher voltages.  The number of disks is chosen based on line voltage, lightning withstand  requirement, altitude, and environmental factors such as fog, pollution, or salt spray. In cases where these conditions are suboptimal, longer insulators must be used. Longer insulators with longer creepage distance for leakage current, are required in these cases. Strain insulators must be strong enough mechanically to support the full weight of the span of conductor, as well as loads due to ice accumulation, and wind.

Porcelain insulators may have a semi-conductive glaze finish, so that a small current (a few milliamperes) passes through the insulator.  This warms the surface slightly and reduces the effect of fog and dirt accumulation.  The semiconducting glaze also ensures a more even distribution of voltage along the length of the chain of insulator units.

Polymer insulators by nature have hydrophobic characteristics providing for improved wet performance. Also, studies have shown that the specific creepage distance required in polymer insulators is much lower than that required in porcelain or glass. Additionally, the mass of polymer insulators (especially in higher voltages) is approximately 50% to 30% less than that of a comparative porcelain or glass string. Better pollution and wet performance is leading to the increased use of such insulators.

Insulators for very high voltages, exceeding 200 kV, may have grading rings installed at their terminals.  This improves the electric field distribution around the insulator and makes it more resistant to flash-over during voltage surges.

Conductors

The most common conductor in use for transmission today is aluminum conductor steel reinforced (ACSR). Also seeing much use is all-aluminum-alloy conductor (AAAC). Aluminum is used because it has about half the weight of a comparable resistance copper cable (though larger diameter due to lower specific conductivity), as well as being cheaper.
Copper was more popular in the past and is still in use, especially at lower voltages and for grounding.

While larger conductors lose less energy due to lower electrical resistance, they are more costly than smaller conductors.  An optimization rule called Kelvin's Law states that the optimum size of conductor for a line is found when the cost of the energy wasted in the conductor is equal to the annual interest paid on that portion of the line construction cost due to the size of the conductors. The optimization problem is made more complex by additional factors such as varying annual load, varying cost of installation, and the discrete sizes of cable that are commonly made.

Since a conductor is a flexible object with uniform weight per unit length, the shape of a conductor strung between two towers approximates that of a catenary. The sag of the conductor (vertical distance between the highest and lowest point of the curve) varies depending on the temperature and additional load such as ice cover. A minimum overhead clearance must be maintained for safety. Since the temperature and therefore length of the conductor increase with increasing current through it, it is sometimes possible to increase the power handling capacity (uprate) by changing the conductors for a type with a lower coefficient of thermal expansion or a higher allowable operating temperature.

Two such conductors that offer reduced thermal sag are known as composite core conductors (ACCR and ACCC conductor).  In lieu of steel core strands that are often used to increase overall conductor strength, the ACCC conductor uses a carbon and glass fiber core that offers a coefficient of thermal expansion about 1/10 of that of steel.  While the composite core is nonconductive, it is substantially lighter and stronger than steel, which allows the incorporation of 28% more aluminum (using compact trapezoidal-shaped strands) without any diameter or weight penalty.  The added aluminum content helps reduce line losses by 25 to 40% compared to other conductors of the same diameter and weight, depending upon electric current.  The carbon core conductor's reduced thermal sag allows it to carry up to twice the current ("ampacity") compared to all-aluminum conductor (AAC) or ACSR.

The power lines and their surroundings must be maintained by linemen, sometimes assisted by helicopters with pressure washers or circular saws which may work three times faster. However this work often occurs in the dangerous areas of the Helicopter height–velocity diagram, and the pilot must be qualified for this "human external cargo" method.

Bundle conductors

For transmission of power across long distances, high voltage transmission is employed. Transmission higher than 132 kV poses the problem of corona discharge, which causes significant power loss and interference with communication circuits. To reduce this corona effect, it is preferable to use more than one conductor per phase, or bundled conductors.

Bundle conductors consist of several parallel cables connected at intervals by spacers, often in a cylindrical configuration. The optimum number of conductors depends on the current rating, but typically higher-voltage lines also have higher current. American Electric Power is building 765 kV lines using six conductors per phase in a bundle. Spacers must resist the forces due to wind, and magnetic forces during a short-circuit.

Bundled conductors reduce the voltage gradient in the vicinity of the line. This reduces the possibility of corona discharge. At extra high voltage, the electric field gradient at the surface of a single conductor is high enough to ionize air, which wastes power, generates unwanted audible noise and interferes with communication systems.  The field surrounding a bundle of conductors is similar to the field that would surround a single, very large conductor—this produces lower gradients which mitigates issues associated with high field strength. The transmission efficiency is improved as loss due to corona effect is countered.

Bundled conductors cool themselves more efficiently due to the increased surface area of the conductors, further reducing line losses. When transmitting alternating current, bundle conductors also avoid the reduction in ampacity of a single large conductor due to the skin effect. A bundle conductor also has lower reactance, compared to a single conductor.

While wind resistance is higher, wind-induced oscillation can be damped at bundle spacers. The ice and wind loading of bundled conductors will be greater than a single conductor of the same total cross section, and bundled conductors are more difficult to install than single conductors.

Ground wires

Overhead power lines are often equipped with a ground conductor (shield wire, static wire, or overhead earth wire). The ground conductor is usually grounded (earthed) at the top of the supporting structure, to minimize the likelihood of direct lightning strikes to the phase conductors. In circuits with earthed neutral, it also serves as a parallel path with the earth for fault currents. Very high-voltage transmission lines may have two ground conductors. These are either at the outermost ends of the highest cross beam, at two V-shaped mast points, or at a separate cross arm. Older lines may use surge arresters every few spans in place of a shield wire; this configuration is typically found in the more rural areas of the United States. By protecting the line from lightning, the design of apparatus in substations is simplified due to lower stress on insulation. Shield wires on transmission lines may include optical fibers (optical ground wires/OPGW), used for communication and control of the power system.

At some HVDC converter stations, the ground wire is used also as the electrode line to connect to a distant grounding electrode. This allows the HVDC system to use the earth as one conductor. The ground conductor is mounted on small insulators bridged by lightning arrestors above the phase conductors. The insulation prevents electrochemical corrosion of the pylon.

Medium-voltage distribution lines may also use one or two shield wires, or may have the grounded conductor strung below the phase conductors to provide some measure of protection against tall vehicles or equipment touching the energized line, as well as to provide a neutral line in Wye wired systems.

On some power lines for very high voltages in the former Soviet Union, the ground wire is used for PLC systems and mounted on insulators at the pylons.

Insulated conductors and cable
Overhead insulated cables are rarely used, usually for short distances (less than a kilometer). Insulated cables can be directly fastened to structures without insulating supports.  An overhead line with bare conductors insulated by air is typically less costly than a cable with insulated conductors.

A more common approach is "covered" line wire. It is treated as bare cable, but often is safer for wildlife, as the insulation on the cables increases the likelihood of a large-wing-span raptor to survive a brush with the lines, and reduces the overall danger of the lines slightly. These types of lines are often seen in the eastern United States and in heavily wooded areas, where tree-line contact is likely. The only pitfall is cost, as insulated wire is often costlier than its bare counterpart. Many utility companies implement covered line wire as jumper material where the wires are often closer to each other on the pole, such as an underground riser/pothead, and on reclosers, cutouts and the like.

Dampers

Because power lines can suffer from aeroelastic flutter driven by wind, Stockbridge dampers are often attached to the lines to reduce the vibrations.

Compact transmission lines

A compact overhead transmission line requires a smaller right of way than a standard overhead powerline. Conductors must not get too close to each other. This can be achieved either by short span lengths and insulating crossbars, or by separating the conductors in the span with insulators. The first type is easier to build as it does not require insulators in the span, which may be difficult to install and to maintain.

Examples of compact lines are:
 Lutsk compact overhead powerline
 Hilpertsau-Weisenbach compact overhead line

Compact transmission lines may be designed for voltage upgrade of existing lines to increase the power that can be transmitted on an existing right of way.

Low voltage

Low voltage overhead lines may use either bare conductors carried on glass or ceramic insulators or an aerial bundled cable system. The number of conductors may be anywhere between two (most likely a phase and neutral) up to as many as six (three phase conductors, separate neutral and earth plus street lighting supplied by a common switch); a common case is four (three phase and neutral, where the neutral might also serve as a protective earthing conductor).

Train power

Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains. Overhead line is designed on the principle of one or more overhead wires situated over rail tracks. Feeder stations at regular intervals along the overhead line supply power from the high-voltage grid. For some cases low-frequency AC is used, and distributed by a special traction current network.

Further applications
Overhead lines are also occasionally used to supply transmitting antennas, especially for efficient transmission of long, medium and short waves. For this purpose a staggered array line is often used. Along a staggered array line the conductor cables for the supply of the earth net of the transmitting antenna are attached on the exterior of a ring, while the conductor inside the ring, is fastened to insulators leading to the high-voltage standing feeder of the antenna.

Use of area under overhead power lines
Use of the area below an overhead line is limited because objects must not come too close to the energized conductors. Overhead lines and structures may shed ice, creating a hazard. Radio reception can be impaired under a power line, due both to shielding of a receiver antenna by the overhead conductors, and by partial discharge at insulators and sharp points of the conductors which creates radio noise.

In the area surrounding the overhead lines it is dangerous to risk interference; e.g. flying kites or  balloons, using ladders or operating machinery.

Overhead distribution and transmission lines near airfields are often marked on maps, and the lines themselves marked with conspicuous plastic reflectors, to warn pilots of the presence of conductors.

Construction of overhead power lines, especially in wilderness areas, may have significant environmental effects. Environmental studies for such projects may consider the effect of bush clearing, changed migration routes for migratory animals, possible access by predators and humans along transmission corridors, disturbances of fish habitat at stream crossings, and other effects.

Aviation accidents

General aviation, hang gliding, paragliding, skydiving, balloon, and kite flying must avoid accidental contact with power lines. Nearly every kite product warns users to stay away from power lines. Deaths occur when aircraft crash into power lines. Some power lines are marked with obstruction markers, especially near air strips or over waterways that may support floatplane operations. The placement of power lines sometimes use up sites that would otherwise be used by hang gliders.

History
The first transmission of electrical impulses over an extended distance was demonstrated on July 14, 1729 by the physicist Stephen Gray. The demonstration used damp hemp cords suspended by silk threads (the low resistance of metallic conductors not being appreciated at the time).

However the first practical use of overhead lines was in the context of telegraphy. By 1837 experimental commercial telegraph systems ran as far as  20 km (13 miles).   Electric power transmission was accomplished in 1882 with the first high-voltage transmission between Munich and Miesbach (60 km). 1891 saw the construction of the first three-phase alternating current overhead line on the occasion of the International Electricity Exhibition in Frankfurt, between Lauffen and Frankfurt.

In 1912 the first 110 kV-overhead power line entered service followed by the first 220 kV-overhead power line in 1923. In the 1920s RWE AG built the first overhead line for this voltage and in 1926 built a Rhine crossing with the pylons of Voerde, two masts 138 meters high.

In 1953, the first 345 kV line was put into service by American Electric Power in the United States. In Germany in 1957 the first 380 kV overhead power line was commissioned (between the transformer station and Rommerskirchen). In the same year the overhead line traversing of the Strait of Messina went into service in Italy, whose pylons served the Elbe crossing 1. This was used as the model for the building of the Elbe crossing 2 in the second half of the 1970s which saw the construction of the highest overhead line pylons of the world. Earlier, in 1952, the first 380 kV line was put into service in Sweden, in 1000 km (625 miles) between the more populated areas in the south and the largest hydroelectric power stations in the north.
Starting from 1967 in Russia, and also in the USA and Canada, overhead lines for voltage of 765 kV were built. In 1982 overhead power lines were built in Soviet Union between Elektrostal and the power station at Ekibastuz, this was a three-phase alternating current line at 1150 kV (Powerline Ekibastuz-Kokshetau). In 1999, in Japan the first powerline designed for 1000 kV with 2 circuits were built, the Kita-Iwaki Powerline. In 2003 the building of the highest overhead line commenced in China, the Yangtze River Crossing.

Mathematical analysis
An overhead power line is one example of a transmission line. At power system frequencies, many useful simplifications can be made for lines of typical lengths. For analysis of power systems, the distributed resistance, series inductance, shunt leakage resistance and shunt capacitance can be replaced with suitable lumped values or simplified networks.

Short and medium line model
A short length of a power line (less than 80 km) can be approximated with a resistance in series with an inductance and ignoring the shunt admittances. This value is not the total impedance of the line, but rather the series impedance per unit length of line. For a longer length of line (80–250 km), a shunt capacitance is added to the model. In this case it is common to distribute half of the total capacitance to each side of the line. As a result, the power line can be represented as a two-port network, such as with ABCD parameters.

The circuit can be characterized as

where
Z is the total series line impedance
z is the series impedance per unit length
l is the line length
 is the sinusoidal angular frequency
The medium line has an additional shunt admittance

where
Y is the total shunt line admittance
y is the shunt admittance per unit length

See also
 Aerial cable
 Conductor marking lights
 CU project controversy
 Overhead cable
 Overhead line
 Raptor conservation
 Third rail
 Operation Outward
 Powerline river crossings in the United Kingdom
 Wireless monitoring of overhead power lines

References

Further reading

 William D. Stevenson, Jr. Elements of Power System Analysis Third Edition, McGraw-Hill, New York (1975)

External links

Electric power distribution

Overhead power line


The Danish Freedom Council () was a clandestine body set up in September 1943 in response to growing political turmoil surrounding the occupation of Denmark by German forces during the Second World War.

Background

Technically, Denmark was illegally occupied by the Germans through Operation Weserübung on 9 April 1940.  The Danish government as well as King Christian X immediately made formal protests but ultimately acquiesced to a unique German arrangement whereby Denmark was given 'independence' despite having German troops stationed in the country. Concerned about the safety of the population, the Danish government thought it best to accept these terms.

As a result, resistance initiatives could not be formally recognised by the Allied forces. Although the Danish government in Copenhagen had accepted the situation, many Danes had not.  Much of the Danish Navy had sailed to Allied ports and Danish ambassadors abroad had refused to accept their government's decision.

A Danish resistance movement arose at the initiative of citizens and former Danish soldiers.  Initially the movement was willing to pass intelligence on to the Special Operations Executive (SOE) but refused to follow the SOE's calls for sabotage operations. Any sabotage that did take place was sanctioned by resistance leaders within Denmark or based in Stockholm. There was an increase in acts of sabotage in Denmark from 1943 on.  Field Marshal Montgomery later stated that intelligence from Danish resistance had been "second to none".

Up to 1943, the occupation was relatively quiet. However, Danish acts of sabotage caused the Germans to harden their response, arresting those involved. This led to strikes, more arrests for civil disobedience, causing even more strikes.

By August 1943, the situation had become so bad, that the Germans sent the Danish government an ultimatum — they were to declare a state of emergency and they were to condemn to death all captured saboteurs. The government refused to do this and resigned. The Germans responded by formally seizing power and, legally, Denmark became an "occupied country", adding to the legitimacy of the Danish Resistance.

Anti-Nazi sentiment sharpened further when the Germans attempted to arrest the Danish Jews in October 1943. The operation failed thanks to Danish assistance in helping over 7,000 of them to escape to Sweden.

The Freedom Council

In September 1943, the 'Danish Freedom Council' was created to co-ordinate the fight for liberation. The Council set out to unify the many different groups that made up the Danish resistance movement and consisted of representatives from the Communists, Free Denmark, Danish Unity and a resistance group called the Ring. Key members were , Mogens Fog, Arne Sørensen, Frode Jakobsen, Erling Foss and . Directives from the British Special Operations Executive helped to unite the different groups.

In December that year, the SOE sent orders that military groups should be organised, ready to attack the Germans in case of invasion. They were first organised by the Communists and the Danish Unity Party, and then increasingly by members of the Ring.

The resistance movement grew to over 20,000 and in the lead-up to D-Day acts of sabotage markedly increased. Though the D-Day landings were to be in Normandy, the SOE encouraged tying up German troops elsewhere in Europe so that the fewer would be present in northern France. If acts of sabotage were increased, more German troops would be tied up in Denmark.

The Danish Resistance used the country's proximity to Sweden to great effect. Stockholm became a base for the Danish Resistance. Here they were far safer than in Denmark — but they could easily get back to their country.

See also

BOPA
Holger Danske (resistance group)

References

Sources
 Hæestrup, Jørgen. Secret Alliance - A Study of the Danish Resistance Movement 1940-45. Vols I, II & III. Odense University Press, 1976-77. ,  & .
 Moore, Bob (editor). Resistance in Western Europe (esp. Chapter on Denmark by Hans Kirchoff), Oxford : Berg, 2000, .

Danish Freedom Council
Danish Freedom Council
Freedom Council

Danish Freedom Council


Henri Adrien Marie Verbrugghen (1 August 187312 November 1934) was a Belgian musician, who directed orchestras in England, Scotland, Australia and the United States.

Born in Brussels, Verbrugghen made his first appearance as a violinist when only eight years old, and was a successful student at the Brussels Conservatorium under Hubay and Ysaÿe, winning many prizes. He visited England with Ysaÿe in 1888, and in 1893 settled in Scotland as a member of the Scottish Orchestra. During the summer he led the orchestra at Llandudno under Jules Riviere. For a time he was a member of the Lamoureux Orchestra at Paris and then for three years was deputy-conductor at Llandudno. He was director of music for four years at Colwyn Bay, and then returned to the Scottish Orchestra.

In 1902 he became leader and deputy-conductor under Frederic Cowen, and during the promenade season led the Queen's Hall Orchestra for three years.

In 1907, he was the soloist in the first performance in England of the Violin Concerto in D minor by Jean Sibelius.

He became chief violin professor at the Athenaeum, Glasgow, and in 1911 succeeded Dr Coward as conductor of the Glasgow Choral Union. In April 1914 he enhanced his growing reputation when a Beethoven Festival was held at London, Verbrugghen "conducting throughout the festival with insight and masterly ability" (The Musical Times, 1 June 1914, p. 399). Early in 1915 he was appointed director of the New South Wales State Conservatorium at a salary of £1,250 a year.

Verbrugghen arrived in Sydney in the same year full of enthusiasm. He had a great admiration for English-speaking people but did not like the methods of their schools of music, and decided that the conservatorium at Sydney should be based on continental models. He got together a remarkably fine orchestra, including the other members of his excellent string quartet who had come with him. For six years Verbrugghen's influence on the musical life of Sydney was of outstanding importance, but the politicians had not realized that it is impossible to carry on work of this nature without financial loss. The orchestra was disbanded in 1921 and Verbrugghen, who had suffered much from worry, went to America for health reasons.

In 1922 he was a guest conductor of the Minneapolis Symphony Orchestra, and had such a brilliant success that he was given the position of permanent conductor. Efforts were made in Australia to persuade him to return without success. In 1927 he composed his Missa de Sancta Maria Magdalena for the choir of St Mary's Basilica in Minneapolis, which is still popular in various congregations in the Midwest which celebrate the Tridentine Latin Mass. In 1928, he was elected a national honorary member of Phi Mu Alpha Sinfonia fraternity, the American fraternity for men in music. In 1931 he collapsed at a rehearsal of his orchestra, and never completely recovered his health. From September 1933 he was chairman of the Department of Music at Carleton College, Northfield, Minnesota, and he died in 1934.

There is a Verbrugghen Street in the suburb of Melba in the Australian national capital, Canberra.  All the streets in the suburb are named after significant figures in Australian music. Verbrugghen Hall at the Sydney Conservatorium of Music in Sydney also commemorates his name.

References

Sources

Belgian conductors (music)
Belgian male musicians
Male conductors (music)
Belgian classical violinists
Male classical violinists
Academic staff of the Sydney Conservatorium of Music
1873 births
1934 deaths

Henri Verbrugghen


Altentreptow () is a town in the Mecklenburgische Seenplatte Rural District, in Mecklenburg-Western Pomerania, Germany.  Altentreptow is the chief town of the Treptower Tollensewinkel amt.

It is on the river Tollense,  north of Neubrandenburg and  south of Greifswald.

Name
The town was called Trybethowe in 1175. From 1191 it was being called Trebutowe, and Tributowe in 1245. The name Treptow was being used is 1254. In 1295 the Latin Antiquum Treptow was used. This means Old Treptow, or in

Until 1939 the city's name was Treptow an der Tollense (Treptow on the Tollense).

Fires
The town was burned down several time in the 1500s. Later, during the Thirty Years War the Holy Roman Empire's army was forced to leave the town by the Swedish Army. Later Prussian troops returned, threw the Swedes out, and looted (robbed) the town.

The modern town
By the 18th century wars had made the town very poor. The city wall was taken down to get new land for growing food.

1869 a new city hall was built and there were cloth weavers and spinning mills as well as farmers in the city.

Later a new mill, but this was burned down ´in 1999. A railway line connected the town with Neubrandenburg and Stralsund, and a school, a bank, a hospital and a post office were opened.

1888 a dairy cooperative was started, and they opened new building in 1995.

Electricity arrived in the city in 1916. This encouraged more people to move to the city and build.

The official name of the city was Treptow an der Tollense until 26 January 1939.

A big residential area arose with 1049 flats was built between 1960 and 1985. In the middle of the 1960s the old primary school was changed to a home for old people and a zoo was opened in 1972.

Altentreptow was the capital of the Landkreis (administrative district) Altentreptow from 1952 to 1994.

After the German reunification the old town centre was rebuilt. A modern hospital was opened with 108 beds in 2001.

Twin town
  Meldorf

Culture and sights
 This newly repaired historical old town with the Little Tollense River, the market place and the town gates. The half-timbered houses at Oberbaustraße 26 were built in 1663 and 1823.
 The St. Petri church was built in the 14th and 15th centuries
 Two gates from the old town wall still exist. The Brandenburg Gate and the Demminer Gate were built in 1450.
 The Fritz Reuter House. (The writer Fritz Reuter lived and worked in the town from 1850 to 1856).
 The fountain on the market. Water sprays in all directions
 The city hall of 1869 in the neo-Gothic style.
 The meadow landscape along the Tollense.
 The cloister mountain steeped in history with facilities for culture, leisure time, sports and relaxation.

References

Other websites

Demmin Rural District

Altentreptow


Korydallos Prison Complex is Greece's largest jail and contains the country's main maximum-security prison (Type B), housing both maximum-security men and women. It is located in Korydallos, Piraeus. Famous detainees include members of the anarchist urban guerrilla organizations Revolutionary Organization 17 November, Revolutionary Struggle and Conspiracy of Fire Nuclei. Korydallos prison was also used as the place for the Greek junta trials in 1975, and contains a special court in its basement.

Nikolaos Dertilis was the last remaining junta member in jail. He died 28 January 2013 at the age of 94.

Conditions of detention
Amnesty International and other human rights bodies such as the Committee for the Prevention of Torture have repeatedly expressed concern about the prison for its overcrowding and inhumane treatment of detainees.
In 2007, a special committee composed of physicians of the Division of Health Inspections of the Prefecture of Piraeus and Piraeus Medical Association has reported that the hospital and the mental clinic of the prison operate without even the minimum conditions of hygiene, with aging infrastructure and big shortages in medical and nursing staff. The Hellenic Parliament has vowed to improve conditions.
Since May 2008 the women prisoners section has been transferred to Thiva prison complex following many years of protests and complaints to the government by the Korydallos municipality and inhabitants. As of only one of the three women prison section hosts women under trial.  Demolition works have commenced, for the two out of the three sections, in January 2010 and although they were expected to be completed till the end of June 2010, leaving free space of  to be used as a park, the demolition was completed about 7 years after, in March 2017.

== Prisoner actions ==
In November 1995, there was a massive riot, with inmates taking control of the prison for several days in a "battle" with prison guards and police.
Earlier in 1990, the inmates of Korydalos took over the entire complex for 28 days. The seizure of the complex was related to prison conditions and criminal justice reform. After the 28 day standoff, Justice officials bent to a majority of the demands the prisoners made and concessions were given in favor of the inmates.

There have been several politically motivated attacks in relation to Korydallos prison, including; On 13 May 2010, a bomb exploded outside the prison injuring a member of the public. Police suspected Revolutionary Struggle. In 2013, a bomb containing 1 kg of dynamite was left under the car of the governor of Korydallos Prison outside his home in Dafni, Athens. The attack was claimed by the Conspiracy of Fire Nuclei as "a show of solidarity for our 10 imprisoned brothers". And in 2016, a bomb exploded next to a prison officer's car at his home. The attack was reported as an attempt of intimidation.

In February 2008 a group of political inmates held a sit-down protest against the transfer of an anarchist prisoner to another prison. Among the protesters was N17 prisoner Dimitris Koufontinas.

In January 2021 Dimitris Koufontinas, then 63 year old prisoner convicted of crimes as part of November 17 Organization performed a 66 day hunger strike with the goal of being sent to Korydallos prison. Street demonstrations were held in multiple cities across Greece as well as attacks against property has been claimed in support of Koufontinas, Koufontinas ended the hunger strike after 66 days without his demands having been met.

Notable Inmates and Escapes
Inmate Vasilis Paleokostas, known popularly as the 'Greek Robin Hood' drew attention to the prison when he escaped with a rented helicopter, twice in June 2006 and February 2009.

In January 2014 Christodoulos Xiros of 17 November Organization whilst serving multiple life sentences escaped after being granted temporary leave to see his family in the north of the country only to not return. Xiros was captured a year later allegedly preparing further guerrilla actions including aiding other prisoners in escape.

Nikolaos Maziotis, the reported leader of the urban guerrilla organization, Revolutionary Struggle disappeared in April 2014 during his trial at Korydallos prison. Maziotis was captured in July 2014 after a shootout with police in Central Athens during a robbery, leaving himself and two others including one police officer injured. In 2016 Maziotis again attempted escape when romantic partner and comrade in Revolutionary Struggle, Pola Roupa, unsuccessfully attempted to help Maziotis along with other political prisoners escape via a hijacked helicopter.

Human rights activist Sarah Mardini was incarcerated at Korydallos during 106 days in pre-trail detention, after being arrested for various crimes in 2018.

References

Prisons in Greece
Piraeus (regional unit)
Buildings and structures in Attica

Korydallos Prison


Robert O'Hara Burke (6 May 1821c. 28 June 1861) was an Irish soldier and police officer who achieved fame as an Australian explorer. He was the leader of the ill-fated Burke and Wills expedition, which was the first expedition to cross Australia from south to north, finding a route across the continent from the settled areas of Victoria to the Gulf of Carpentaria. The expedition party was well equipped, but Burke was not experienced in bushcraft. A Commission of Inquiry held by the Government of Victoria to investigate the failure of the expedition was a censure of Burke's judgement.

Early years
Burke was born in St Clerans, County Galway, Ireland in May 1821. He was the second of three sons of James Hardiman Burke (1788 – January 1854), an officer in the British army 7th Royal Fusiliers, and Anne Louisa Burke née O'Hara (married 1817, d.1844).

Robert O'Hara was one of seven children;
 John Hardiman Burke (d. August 1863)
 Robert O'Hara Burke (6 May 1821 – 28 June 1861)
 James Thomas Burke (c. 1828 – 7 July 1854)
 Fanny Marie Burke (married John Blakeney)
 Elizabeth Burke (married Lt. Col Menzies)
 Hester Albinia Burke (unmarried, d. 10 November 1866)
 Anne Celestine Burke (married Major Horace de Vere, d.1914)

James Thomas Burke was a Lieutenant in the Royal Engineers, and on 7 July 1854 at the battle of Giurgevo became the first British officer killed in the Crimean war.

Military career
Burke entered the Royal Military Academy, Woolwich in May 1835. In December 1836 he failed his probationary exam and went to Belgium to further his education. In 1841, at the age of twenty he entered the Austrian army and in August 1842 was promoted to Second Lieutenant in the Prince Regent's 7th Reuss Regiment of the Hungarian Hussars. He spent most of his time in the Imperial Austrian Army posted to northern Italy and in April 1847 was promoted to 1st Lieutenant. Towards the end of 1847 he suffered health problems and went to Recoaro spa in northern Italy, then Gräfenberg (now Lázně Jeseník) and finally Aachen before resigning from the Austrian army in June 1848 after charges against him relating to debts and absence without leave were dropped.

Police career
After returning to Ireland in 1848, he joined the Irish Constabulary (later the Royal Irish Constabulary). He did his cadet training at Phoenix Park Depot in Dublin between November 1849 and January 1850, was promoted to 3rd Class Sub-Inspector and he was stationed in County Kildare. At the end of 1850, he transferred to the Mounted Police in Dublin.

Migrating to Australia
Burke migrated to Australia in 1853. He left Queenstown, County Cork on 24 November 1852 on the S.S. Rodney which was carrying 342 convicts. He arrived in Hobart, Tasmania on 12 February 1853 and promptly sailed for Melbourne. On 1 April 1853 he joined the recently established Victoria police force. Initially, he worked as Acting Inspector under the Chief Commissioner William Henry Fancourt Mitchell in the Parish of Jika Jika in the northern suburbs of Melbourne, but on 1 November 1853 he was appointed a magistrate, was promoted to Police Inspector, and was posted to Carlsruhe. On 31 December 1853 he was promoted to District Inspector of the Ovens District and early in 1854 he moved to Beechworth to relieve Inspector John Giles Price.

After the unfortunate death of his brother, James Thomas, in the Crimean War, Burke decided to enlist. He left Australia on the S.S. Marco Polo on 25 March 1856 for England, but, by the time he arrived in Liverpool in June, peace had been declared and the war ended. Burke re-boarded the Marco Polo and returned to Victoria, arriving in Melbourne on 2 December 1856.

He resumed his posting at Beechworth and from there attended the "Buckland Valley" riots near Bright against the Chinese gold miners in 1857. In November 1858 he was transferred to Castlemaine as Police Superintendent on £550 p.a. plus a groom and quarters at Broadoaks on Gingell Street.

After the South Australian explorer, John McDouall Stuart had reached the centre of Australia, the South Australian parliament offered a reward of £2,000 for the promotion of an expedition to cross the continent from the south to north, generally following Stuart's route. He also partnered with another explorer who wanted to discover things about Australia.

Burke and Wills Expedition

In June 1860, Burke was appointed to lead the Victorian Exploring Expedition with William John Wills, his third-in-command, as surveyor and astronomical observer.

The expedition left Melbourne on Monday, 20 August 1860 with a total of 19 men, 27 camels and 23 horses. They reached Menindee on 23 September 1860 where several people resigned, including the second-in-command, George James Landells and the medical officer, Dr. Hermann Beckler.

Cooper Creek, 400 miles further on, was reached on 11 November 1860 by the advance group, the remainder being intended to catch up. After a break, Burke decided to make a dash to the Gulf of Carpentaria, leaving on 16 December 1860. William Brahe was left in charge of the remaining party. The small team of Burke, William Wills, John King and Charley Gray reached the mangroves on the estuary of the Flinders River, near where the town of Normanton now stands, on 9 February 1861. Flooding rains and swamps meant they never saw open ocean.

Already weakened by starvation and exposure, their progress on the return journey was slow and hampered by the tropical monsoon downpours of the wet season. Gray died four days before they reached the rendezvous at Cooper Creek.
The other three rested for a day when they buried him.
They eventually reached the rendezvous point on 21 April 1861, 9 hours after the rest of the party had given up waiting and left, leaving a note and some food, as they had not been relieved by the party supposed to be returning from Menindee.

They attempted to reach Mount Hopeless, the furthest outpost of pastoral settlement in South Australia, which was closer than Menindee, but failed and returned to Cooper Creek. While waiting for rescue Wills died of exhaustion and starvation. Soon after, Burke also died, at a place now called Burke's Waterhole on Cooper Creek in South Australia. The exact date of Burke's death is uncertain, but has generally been accepted to be 28 June 1861.

King survived with the help of Aborigines until he was rescued in September by Alfred William Howitt. Howitt buried Burke and Wills before returning to Melbourne. In 1862 Howitt returned to Cooper Creek and disinterred Burke and Wills' bodies, taking them first to Adelaide and then by steamer to Melbourne where they were laid in state for two weeks. On 23 January 1863, Burke and Wills received a state funeral and were buried in Melbourne General Cemetery. On that day, Stuart and his companions, having successfully completed the south–north crossing, were received back at a large ceremony in Adelaide.

Places named after Burke

Burketown, Queensland
Burke River in western Queensland.
O'Haras Gap, Selwyn Ranges, Queensland.

Places named by Burke
Cloncurry River was named by Burke after Lady Cloncurry. She was his cousin, Elizabeth Kirwan, who had married Lord Cloncurry. Lady Cloncurry was the daughter of Burke's paternal Aunt Penelope and her husband John Kirwan.

See also

 John King (explorer)
 List of people on stamps of Ireland
 William John Wills

Notes

References

Kathleen Fitzpatrick, 'Burke, Robert O'Hara (1821–1861)', Australian Dictionary of Biography, Volume 3, MUP, 1969, pp 301–303.

The [Melbourne] Argus, 1861. "The Burke and Wills exploring expedition: An account of the crossing the continent of Australia from Cooper's Creek to Carpentaria, with biographical sketches of Robert O'Hara Burke and William John Wills". Melbourne: Wilson and Mackinnon.
Bonyhady, Tim, 1991. Burke and Wills: From Melbourne to myth. Balmain: David Ell Press. .
Burke and Wills Outback Conference 2003, 2005. The Inaugural Burke & Wills Outback Conference : Cloncurry 2003 : a collation of presentations. Dave Phoenix, Cairns Qld.
Clune, Frank, 1937. Dig: A drama of central Australia. Sydney: Angus and Robertson.
Corke, David G, 1996. The Burke and Wills Expedition: A study in evidence. Melbourne: Educational Media International.
Henry, William, 1997. The shimmering waste: The life and times of Robert O'Hara Burke. Galway, Ireland.: W Henry Publisher.
Howitt, Alfred William, 1907. "Personal reminiscences of Central Australia and the Burke and Wills Expedition: Presidents inaugural address". Journal of the Australasian Association for the Advancement of Science. 1907  (Adelaide, 1907.), 43p.
Jackson, Andrew, 1862. Robert O'Hara Bourke [sic] and the Australian Exploring Expedition of 1860. London: Smith, Elder & Co.
Manwaring, William Henry, 1970. "A contemporary's view of Robert O'Hara Burke". La Trobe Library Journal. Vol. 2  (No. 6).
Moorehead, Alan, 1963. Cooper's Creek. New York and Evanston: Harper & Row, Publishers, 1963.
Murgatroyd, Sarah, 2002. The Dig Tree. Melbourne: Text Publishing.
Victoria: Parliament, 1862. Burke and Wills Commission. Report of the Commissioners appointed to enquire into and report upon the circumstances connected with the sufferings and death of Robert O'Hara Burke and William John Wills, the Victorian Explorers. Melbourne: John Ferres Government Printer.
Wills, William John, & Wills, Dr William, 1863. A successful exploration through the interior of Australia, from Melbourne to the Gulf of Carpentaria: from the journals and letters of William John Wills. London: Richard Bentley.

External links

 Burke & Wills Web A comprehensive website containing many of the historical documents relating to the Burke & Wills Expedition.
 The Burke & Wills Historical Society The Burke & Wills Historical Society.

1821 births
1861 deaths
Australian people of Anglo-Irish descent
Irish Anglicans
19th-century Irish explorers
Explorers of Australia
Explorers from Melbourne
Royal Irish Constabulary officers
Deaths by starvation
Police officers from County Galway
Burke and Wills expedition
Burials at Melbourne General Cemetery
Explorers of Queensland

Robert O'Hara Burke


A Girl for Me (Swedish: En flicka för mej) is a 1943 Swedish comedy film directed by Börje Larsson and starring Sickan Carlsson, Karl-Arne Holmsten and Max Hansen. It was shot at the Sundbyberg Studios in Stockholm. The film's sets were designed by the art director Max Linder.

Cast

 Sickan Carlsson as Vera Lanner
 Karl-Arne Holmsten as Klas Ekengren
 Max Hansen as 	Ambrosius Jensen
 Gull Natorp as 	Lord Mayoress
 Hilda Borgström as Aunt Louise
 Kerstin Lindahl as 	Marianne
 Eric Gustafson as 	Hedlund
 Bror Bügler as 	Halmblad
 Marianne Löfgren as 	Journalist
 Julia Cæsar as 	Mrs. Nilsson
 Artur Rolén as 	Mr. Nilsson
 Willy Peters as 	Klas' Friend
 Åke Engfeldt as 	Klas' Friend
 Åke Jensen as 	Klas' Friend
 Magnus Kesster as 	Barber
 Ragnar Widestedt as 	Major Blom
 Carl Deurell as 	Elder
 Torsten Hillberg as Elder
 Nina Scenna as Therese Hedlund
 Ruth Weijden as Emma
 Stina Ståhle as Mrs. Hedlund
 Wiola Brunius as Gertrud Vesterberg
 Margit Andelius as 	Mrs. Johansson
 Hartwig Fock as Taxi Driver
 Nils Ohlin as 	A Man
 Nils Jacobsson as A Man
 Bertil Berglund as 	Janitor
 Gösta Bodin as 	Cafe owner
 Ernst Brunman as 	Policeman
 Gösta Gustafson as Brinck
 Agneta Lagerfeldt as 	Woman
 Paul Hagman as Man in the audience
 Arne Lindblad as 	Maitre d'
 Ingrid Luterkort as 	Klas' secretary

References

Bibliography
 Qvist, Per Olov & von Bagh, Peter. Guide to the Cinema of Sweden and Finland. Greenwood Publishing Group, 2000.

External links

1943 films
Swedish comedy films
1943 comedy films
1940s Swedish-language films
Films directed by Börje Larsson
1940s Swedish films

A Girl for Me


In mathematics, fuzzy measure theory considers generalized measures in which the additive property is replaced by the weaker property of monotonicity.  The central concept of fuzzy measure theory is the fuzzy measure (also capacity, see ), which was introduced by Choquet in 1953 and independently defined by Sugeno in 1974 in the context of fuzzy integrals.  There exists a number of different classes of fuzzy measures including plausibility/belief measures, possibility/necessity measures, and probability measures, which are a subset of classical measures.

Definitions
Let  be a universe of discourse,  be a class of subsets of , and .  A function  where

is called a fuzzy measure.
A fuzzy measure is called normalized or regular if .

Properties of fuzzy measures

A fuzzy measure is:

 additive if for any  such that , we have ;
 supermodular if for any , we have ;
  submodular if for any , we have ;
  superadditive if for any  such that , we have ;
  subadditive if for any  such that , we have ;
  symmetric if for any , we have  implies ;
  Boolean if for any , we have  or .

Understanding the properties of fuzzy measures is useful in application.  When a fuzzy measure is used to define a function such as the Sugeno integral or Choquet integral, these properties will be crucial in understanding the function's behavior.  For instance, the Choquet integral with respect to an additive fuzzy measure reduces to the Lebesgue integral.  In discrete cases, a symmetric fuzzy measure will result in the ordered weighted averaging (OWA) operator.  Submodular fuzzy measures result in convex functions, while supermodular fuzzy measures result in concave functions when used to define a Choquet integral.

Möbius representation
Let g be a fuzzy measure. The Möbius representation of g is given by the set function M, where for every ,

The equivalent axioms in Möbius representation are:

 .
 , for all  and all

A fuzzy measure in Möbius representation  M is called normalized
if

Möbius representation can be used to give an indication of which subsets of X interact with one another.  For instance, an additive fuzzy measure has Möbius values all equal to zero except for singletons.    The fuzzy measure g in standard representation can be recovered from the Möbius form using the Zeta transform:

Simplification assumptions for fuzzy measures

Fuzzy measures are defined on a semiring of sets or monotone class, which may be as granular as the power set of X, and even in discrete cases the number of variables can be as large as 2|X|.  For this reason, in the context of multi-criteria decision analysis and other disciplines, simplification assumptions on the fuzzy measure have been introduced so that it is less computationally expensive to determine and use.  For instance, when it is assumed the fuzzy measure is additive, it will hold that  and the values of the fuzzy measure can be evaluated from the values on X.  Similarly, a symmetric fuzzy measure is defined uniquely by |X| values.  Two important fuzzy measures that can be used are the Sugeno- or -fuzzy measure and k-additive measures, introduced by Sugeno and Grabisch respectively.

Sugeno λ-measure

The Sugeno -measure is a special case of fuzzy measures defined iteratively. It has the following definition:

Definition
Let   be a finite set and let . A Sugeno -measure is a function  such that

 .
 if  (alternatively ) with  then .

As a convention, the value of g at a singleton set
is called a density and is denoted by . In addition, we have that  satisfies the property

.

Tahani and Keller  as well as Wang and Klir have showed that once the densities are known, it is possible to use the previous polynomial to obtain the values of  uniquely.

k-additive fuzzy measure

The k-additive fuzzy measure limits the interaction between the subsets  to size .  This drastically reduces the number of variables needed to define the fuzzy measure, and as k can be anything from 1 (in which case the fuzzy measure is additive) to X, it allows for a compromise between modelling ability and simplicity.

Definition

A discrete fuzzy measure g on a set X is called k-additive () if its Möbius representation verifies , whenever  for any , and there exists a subset F with k elements such that .

Shapley and interaction indices

In game theory, the Shapley value or Shapley index is used to indicate the weight of a game.  Shapley values can be calculated for fuzzy measures in order to give some indication of the importance of each singleton.  In the case of additive fuzzy measures, the Shapley value will be the same as each singleton.

For a given fuzzy measure g, and , the Shapley index for every  is:

The Shapley value is the vector

See also
Probability theory
Possibility theory

References

Further reading
 Beliakov, Pradera and Calvo, Aggregation Functions: A Guide for Practitioners, Springer, New York 2007.
 Wang, Zhenyuan, and, George J. Klir, Fuzzy Measure Theory, Plenum Press, New York, 1991.

External links
Fuzzy Measure Theory at Fuzzy Image Processing

Exotic probabilities
Measure theory
Fuzzy logic

Fuzzy measure theory


The Nairobi Securities Exchange (NSE) was established  in 1954 as the Nairobi Stock Exchange, based in Nairobi the capital of Kenya. It was a voluntary association of stockbrokers in the European community registered under the Societies Act in British Kenya. The exchange had 66 listed companies in February 2021.

History

Founding Nairobi Stock Exchange (1954-1999)
The Nairobi Stock Exchange was established in 1954 as the in Nairobi, the capital of Kenya. It was a voluntary association of stockbrokers in the European community registered under the Societies Act in British Kenya. Previous to its founding, dealing in shares and stocks started in the 1920s when it was the British colonial Kenya Colony (1920−1963), a part of the British Empire. A stock exchange was first floated in 1922 at the Exchange Bar in the Stanley Hotel in Nairobi. However, the market was not formal as there did not exist any rules and regulations to govern stock broking activities. Trading took place on a 'gentleman's agreement.' Standard commissions were charged with clients being obligated to honor their contractual commitments of making good delivery and settling relevant costs. At that time, stock broking was a sideline business conducted by accountants, auctioneers, estate agents and lawyers who met to exchange prices over a cup of coffee. Because these firms were engaged in other areas of specialization, the need for association did not arise. In 1951, an estate agent named of Francis Drummond established the first professional stock broking firm. He also approached the finance minister of Kenya, Sir Ernest Vasey, and impressed upon him the idea of setting up a stock exchange in East Africa. The two approached London Stock Exchange officials in July 1953 and the London officials accepted to recognize the setting up of the Nairobi Stock Exchange as an overseas stock exchange. In 1954 the Nairobi Stock Exchange was then constituted as a voluntary association of stockbrokers registered under the Societies Act.

Since Africans and Asians were not permitted to trade in securities, until after the attainment of independence in 1963, the business of dealing in shares was confined to the resident European community. At the dawn of independence, stock market activity slumped due to uncertainty about the future of independent Kenya. 1988 saw the first privatization through the NSE with the sale of a 20% government stake in Kenya Commercial Bank. The sale left the Government of Kenya and affiliated institutions retaining 80% ownership of the bank. Notably, on 18 February 1994 the NSE 20-Share Index recorded an all-record high of 5030 points. The NSE was rated by the International Finance Corporation (IFC) as the best performing market in the world with a return of 179% in dollar terms. The NSE also moved to more spacious premises at the Nation Centre in July 1994, setting up a computerized delivery and settlement system (DASS). For the first time since the formation of the Nairobi Stock Exchange, the number of stockbrokers increased with the licensing of eight new brokers.

In 1996 saw the largest share issue in the history of NSE with the privatization of Kenya Airways. Having sold a 26% stake to KLM, the Government of Kenya proceeded to offer 235,423,896 shares (51% of the fully paid and issued shares of KSh.5/= each) to the public at KSh.11/25 per share. More than 110,000 shareholders acquired a stake in the airline and the Government of Kenya reduced its stake from 74% to 23%. The Kenya Airways Privatization team was awarded the World Bank Award for Excellence for 1996 for being a model success story in the divestiture of state-owned enterprises. In 1998 the government expanded the scope for foreign investment by introducing incentives for capital markets growth including the setting up of tax‐free Venture Capital Funds, removal of Capital Gains Tax on insurance companies' investments, allowance of beneficial ownership by foreigners in local stockbrokers and fund managers and the envisaged licensing of Dealing Firms to improve market liquidity. On 1 January 1999, Kenya adopted the International Accounting Standards (IAS) as the local accounting standard.

Expansion (2000–2005)
NSE implemented a new trading cycle, (T+5) in August 2000. The Central Depository System Act (CDS) and the amended CMA Act covering Collective Investment Schemes (CIS) were passed by parliament and affirmed by the president, paving the way for the full implementation of the CDS and for the introduction of collective investment schemes in the Kenyan market. Following a partnership agreement with the Association of National Numbering Agencies (ANNA), the global securities numbering agency, in September 2000 the NSE was appointed the national numbering agency (NNA) for Kenya, making it responsible for issuing the ISIN for financial securities issued under Kenyan jurisdiction in accordance with ANNA's ISO 6166 guidelines. In October 2000 NSE became a member of ANNA.

In April 2002 CMA announced the approval of the new NSE trading and settlement rules. The amount for block trades was revised upwards from Kshs. 3.0 million to between KSh.50 – 200 million/=. The block trade rules now applied to trade values above KSh.50 million/= but less than KSh.200 million/=. Lastly, the brokerage commissions' regime was liberalized. July 2002 saw the foreign investor regulations amended, providing for a 25% minimum reserve of the issued share capital for Kenyan citizens, while the balance of the 75% becomes a free float for all classes of investors. Within this 75% share holding available to all classes of investors, there is no restriction on the amount to be held by a single foreign investor. The signing of the shareholders' agreement for the Central Depository and Settlement Corporation (CDSC) was done in August 2002. The shareholders consisted of the Nairobi Stock Exchange (20%), the Association of Kenya Stockbrokers (18%), the CMA Investor Compensation Fund (7%), and 9 institutional investors through the Capital Markets Challenge Fund (50%) who collectively invested in the CDSC. The CDSC being the legal entity that owns and runs the clearing, settlement, depository and registry system for securities traded in Kenya's capital markets. As of November 2002, the NSE became the sole NNA in Kenya, responsible for allocating the unique code for quoted and unquoted securities domiciled in Kenya.

In March 2003 the CDSC in collaboration with the NSE commenced the CDS Education Campaign in preparation for the market automation. The first CDS Education Workshop, with the theme "The CDS Legal & Regulatory Framework" kicked off. The NSE celebrated its Golden Jubilee in 2004, and also hosted the 8th ASEA conference. In this celebration, the first NSE magazine dubbed "The Exchange" and, The Central Depository & Settlement Corporation (CDSC), which manages Central Depository Systems, were both launched. For the year ending 31 December 2003, the exchange recorded an equity turnover exceeding KSh.15.25 billion/=, more than the combined equity turnover recorded in the previous five years. For the year ending 31 December 2004, the exchange recorded an equity turnover exceeding KSh.22.32 billion/=; an increase of 46.37% over the corresponding period for 2003. For the year ending 31 December 2005, the exchange recorded an equity turnover exceeding KSh.36.52 billion/= (a 63.61% increase over the previous year's performance of Kshs. 22.32 billion).

New technologies and indexes (2006–2010)
In May 2006, NSE formed a demutualisation committee to spearhead the process of demutualisation. A demutualisation consultant (Ernst and Young) was appointed to advise on the process. In September 2006 live trading on the automated trading systems of the Nairobi Stock Exchange was implemented. The ATS was sourced from[Millennium Information Technologies (MIT) of Colombo, Sri Lanka, who are also the suppliers of the Central Depository System (CDS). MIT have also supplied similar solutions to the Colombo Stock Exchange and the Stock Exchange of Mauritius. The NSE ATS solution was customized to uphold the spirit of the open outcry trading rules in an automated environment. In the same breadth, trading hours increased from two (10:00 am – 12:00 pm) to three (10:00 am – 1:00 pm). Other innovations included the removal of the block trades board and introduction of the functionality for the trading of rights in the same manner as equities. Besides trading equities, the ATS trades immobilized corporate bonds and treasury bonds.

An MoU between the Nairobi Stock Exchange and Uganda Securities Exchange was signed in November 2006 on mass cross listing. The MoU allowed listed companies in both exchanges to dualist, to facilitate growth and development of the regional securities markets. In February 2007 NSE upgraded its website, in part to boost data vending business. In July 2007 NSE reviewed the Index and announced the companies that would constitute the NSE Share Index. The review of the NSE 20‐share index was aimed at ensuring it is a true barometer of the market. A wide area network (WAN) platform was implemented in 2007; this eradicated the need for brokers to send their staff (dealers) to the trading floor to conduct business. Trading is now mainly conducted from the brokers' offices through the WAN. However, brokers under certain circumstances can still conduct trading from the floor of the NSE.

In 2008, the NSE All Share Index (NASI) was introduced as an alternative index. Its measure is an overall indicator of market performance. The Index incorporates all the traded shares of the day. Its attention is therefore on the overall market capitalization rather than the price movements of select counters. In April 2008, NSE launched the NSE Smart Youth Investment Challenge to promote stock market investments among Kenyan youth. The objective of the challenge was threefold:
 To occupy the minds of the youth positively and draw them away from the negative energy created by the current political, economic and social situation in the country;
 Encourage the culture of thrift and saving funds amongst the university students;
 Encourage the youth to invest their savings in the capital markets.

After the resignation of Chris Mwebesa, the NSE board appointed Peter Mwangi to be the new NSE chief executive in November 2008. The Complaints Handling Unit (CHU) was launched in August 2009 to bridge the confidence gap with NSE retail investors and have any concerns processed and resolved. Also in 2009,  NSE launched the Complaints Handling Unit (CHU) SMS System. The Nairobi Stock Exchange marked the first day of automated trading in government bonds through the Automated Trading System (ATS) in November 2009. The automated trading in government bonds marked a significant step in the efforts by the NSE and CBK towards creating depth in the capital markets by providing the necessary liquidity. In December 2009, NSE marked a milestone by uploading all government bonds on the ATS.

Nairobi Securities Exchange (2011–2022)
In July 2011, the Nairobi Stock Exchange Limited, changed its name to the Nairobi Securities Exchange Limited.  The change reflected the NSE's strategic plan to become a full service securities exchange supporting trading, clearing and settlement of equities, debt, derivatives and other associated instruments. In the same year, the equity settlement cycle moved from the previous T+4 settlement cycle to the T+3 settlement cycle. This allowed investors who sell their shares to get their money three days later, while buyers have their CDS credited at the same time. In September 2011 the Nairobi Securities Exchange converted from a company limited by guarantee to a company limited by shares and adopted a new Memorandum and Articles of Association reflecting the change. In October 2011, the Broker Back Office system commenced operations, which facilitates internet trading. In November 2011 the FTSE NSE Kenya 15 and FTSE NSE Kenya 25 Indices were launched, after NSE consulted local asset owners and fund managers, focusing on diverse domestic investment in East Africa. In March 2012 the delayed index values of both new indexes were made available on the NSE website www.nse.co.ke.

The NSE became a member of the Financial Information Services Division (FISD) of the Software and Information Industry Association (SIIA) in March 2012. In May 2013, the NSE moved to the Exchange, 55 Westlands Road, Westlands, Nairobi. On 27 June 2014, The Capital Markets Authority proved the listing of the NSE stock through an IPO and subsequently self-list its shares on the Main Investment Market Segment. With the IPO running from 24 July 2014 to 12 August 2014, the listing made the NSE and the Johannesburg Stock Exchange the only self-listed exchanges in Africa. The NSE IPO was oversubscribed by 763.92%, making it the most oversubscribed share offer in the NSE's history. The NSE shares started trading on the Main Investment Market Segment of the exchange on 9 September 2014.

The NSE added two new listings in November 2014, the Flame Tree Group, an FMCG company and Kurwitu Ventures, a Sharia compliant investment company. Both were listed in the Growth Enterprise Market Segment by way of introduction. Effective 11 February 2015, CMC Holdings, Kenya's largest importer of vehicles and largest car-assembly company, was de-listed from the NSE, following its take over by the Al-Futtaim Group, based in the United Arab Emirates. In March 2015, the NSE officially joined the United Nations Sustainable Stock Exchanges (SSE) initiative whereby they made a voluntary pledge to inform their stakeholders of the importance of integrating sustainability in their capital markets.

The bourse had 66 listed companies in February 2021. The exchange's CEO, Geoffrey Odundo, told the press in April 2022 that NSE.NR was looking to purchase stakes in additional bourses in Africa. At the time, it was the fifth biggest bourse in Africa by market capitalization, and owned 5.9% in Tanzania's Dar es Salaam Stock Exchange. In December 2022, the NSE officially linked with seven other different capital markets in Africa, across 14 African companies. That month the NSE also introduced "fractional investing" in Kenyan stocks. It was reported on December 6, 2022, that foreign investors trading at NSE had halved within one week. At the time, the largest four stocks at the NSE by market capitalization were Safaricom, Equity Group, KCB, and EABL.

Types of indices
These include:
 NSE 20 Share Index- Mean of top 20 performing companies under a certain review year
 NSE 25 Share Index- designed to represent performance of kenyan companies listed in the NSE
 NSE All Share Index (NASI)
 FTSE NSE Indices
 Chuley

Regional integration
NSE is a member of the African Securities Exchanges Association, East African Securities Exchanges Association and an affiliate member of World Federation of Exchanges.

Market listings

Subsidiaries and investments
Other than stock and bond trading as the main business of the NSE, the exchange has the following investments:
 NSE Clear Limited - 100% Shareholding - Nairobi, Kenya - Provision of clearing house services for the derivatives/futures exchange.
 Central Depository and Settlement Corporation Limited - 22.5% Shareholding - Nairobi, Kenya - Provision of clearing, settlement and depository services.

Governance and ownership
Nairobi Securities Exchange, as of 2015, was governed by an eleven-person Board of Directors with Kiprono Kittony serving as the Chairman of the group and Geoffrey Odundo as the CEO.

The shares of the Nairobi Securities Exchange are listed and traded on its own main board, under the symbol NSE.  the shareholding in the bourse's stock were as depicted in the table below:

See also
Economy of Kenya
List of African stock exchanges
List of stock exchanges in the Commonwealth of Nations
List of stock exchanges

References

External links
  Website of Nairobi Securities Exchange
 Website of Kenya Capital Markets Authority
 Website of Authorized Data Vendor of Nairobi Securities Exchange
 Transcentury To List

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Stock exchanges in Kenya
Nairobi
Economy of Kenya
Financial services companies established in 1954
1954 establishments in Kenya
1954 establishments in the British Empire
20th century in Nairobi

Nairobi Securities Exchange


Kåre Norvald Lerum (born 4 December 1939) is a Norwegian businessperson and politician.

He was born in Vik and took an education in Stavanger. He was hired as manager in 1976, and was later the chief executive officer, in Lerum in Sogndal, a family company he owned together with his brother Bjarne Lerum. He is also a brother of Gerd Kjellaug Berge. Lerum was succeeded as chief executive officer by Jan Petter Vadheim in 2004. The brothers passed the ownership of the company down to their children in 2005. , Lerum remained a member of the board of directors of Lerum. Lerum is still one of the wealthiest people in Sogndal.

Lerum chaired the employers' organisation Konservesfabrikkenes Landsforening. He was a member of Sogndal municipal council for six years and served as mayor from 1978 to 1982. He initially represented the Conservative Party but later joined the Progress Party in 2002.

Lerum was decorated as a Knight, First Class, of the Royal Norwegian Order of St. Olav in 2005. In 2003, he won a prize from the regional branch of Noregs Mållag.

References

1939 births
Living people
People from Vik
Norwegian businesspeople
Conservative Party (Norway) politicians
Progress Party (Norway) politicians
Mayors of places in Sogn og Fjordane

Kåre Lerum