Trafo nyaéta hiji alat listrik nu kagunaannana pikeun mindahkeun énérgi listrik ti hiji sirkuit ka sirkuit séjénna ngaliwatan gulungan-gulungan kawat anu babarengan diinduksi ku hiji médan magnét.
Hiji trafo diwangun ku hiji inti (biasana tina beusi silikon) sarta dua gulungan tambaga  atawa leuwih nu dibeulitkeun kana inti. Arus bulak-balik dina salah sahiji gulungan ngabangkitkeun;ngawangun médan magnét nu robah-robah dina jero intina, nu mana ahirna ngainduksi (ngarangsang ngabangkitkeun) tegangan dina gulungan liana. Trafo dipaké keur naékkeun atawa nurunkeun tegangan atawa arus listrik, keur ngarobah impedansi, sarta keur nyadiakeun isolasi listrik hiji rangkéan jeung rangkéan nu séjén.

Sawangan
Trafo nyaéta salah sahiji parabot listrik nu pangbasajana. Rarancang dasarna tacan kungsi ganti leuwih ti saratus taun, sok sanajan kitu rarancang katut bahan trafona mah terus dibebenah ogé. Trafo kacida pentingna pikeun transmisi daya, nu ngajadikeun praktisna transmisi jarak jauh. Ieu kauntungan téh teu leupas tina prinsip dina dipilihna  daya arus bulak-balik nalika "Perang Arus" dina ahir 1880-an.
Trafo frékuénsi sora (harita disebut repeating coils) Dimangpaatkeun ku juru taluntik mangsa keur mitembeyan ngamekarkeun tehnologi telepon, ka dieunakeun trafo téh teu pati dimangpaatkeun alatan geus loba pakakas éléktronik séjéna nu mibanda kagunaan saru sarta leuwih hadé. .

Ditempo tina ukuranna trafo dijieun dumasar kabutuhan, aya trafo nu kacida leutik nepikeun kabisa di sumputkeun di jero mikropon.
Nepika trafo nu ukuran gedé naker pikeun ngahubungkeun listrik hiji nagara, nu mibanda kamampuan nepika gigawatt.

 Trafo teubisa dipaké ngarobah arus AC jadi arus DC, kitu deui sabalikna
 Ngarobah tegangan jeung gedéna arus listrik DC
 Ngarobah frekuensi arus listrik AC nu ditarima.
Tapi, trafo mangrupa hiji bagian tina hiji sistim anu ngajalankeun éta kabéh.

Analogi
Trafo bisa diibaratkeun kawas "géarbox" roda dua anu sederhana pikeun ngagambarkeun tegangan jeung arus listrik. Gulungan primér diumpamakeun jeung tempat asupna sarta gulungan skundér diumpamakeun tempat kaluarna.
Dina ieu gambaran, arus téh sarua jeung gancangna muter éta roda ari tegangan tayalian gedéna tanaga anu dipaké pikeun muterkeun éta roda. Dina hiji "géarbox" tanaga mékanis téh (torsi/kakuatan muter dikalikeun jeung gancangna puteran) hasilna konstan (angger) saruan dina tanaga listrik ogé (Tegangan dikalikeun jeung arus) oge hasilan konstan.

Rasio roda gigi ibaratna jeung rasio stép-up atawa stép-down transformator. Transformator stép-up lumaku sacara analog contona ngalaunana roda gigi (anu mana tanaga mékanik dipindahkeun/ditransfer tina roda gigi anu leutik nyaéta nu muterna gancang kana roda gigi gedé anu muterna laun): didieu aya kaayaan nukeurkeun arus (gancangna muter) sedengkeun voltase sarua jeung (torsi), ku ayana ieu kajadian ngatransfer daya tina gulungan primér ka gulungan sekundér anu mibanda leuwih loba leuwih loba jumlah gulunganna. Transformator stép-down digambarkeun sacara analog kujalan pindahna roda gigi (di mana tanaga mékanik ditransfer tina roda gigi gedé ka roda gigi leutik): ieu nukeurkeun tegangan (torsi) pikeun arus (gancangna muter), kujalan ngatransfer daya tina gulungan primer ka gulungan sekundér. Gulungan mibanda puteran anu leuwih saeutik.

Prinsip dasar

Silih ngainduksi
Trafo basajan ilaharna diwangun ku dua konduktor listrik disebut gulungan primér jeung gulungan sekundér. Énergi dihijikeun antara gulungan ku fluks magnét anu béda-béda waktos anu ngalangkungan (tumbu) boh gulungan primér sareng gulungan sekundér. Dimana arus dina coil robah atawa pareum, tegangan anu ngainduksi dina coil tatangga. Pangaruh ieu, disebut mutual induktansi, ieu mangrupa conto induksi éléktromagnétik.

Analisis dasar

If a time-varying voltage  is applied to the primary winding of  turns, a current will flow in it producing a magnetomotive force (MMF). Just as an electromotive force (EMF) drives current around an electric circuit, so MMF tries to drive magnetic flux through a magnetic circuit. The primary MMF produces a varying magnetic flux  in the core, and, with an open circuit secondary winding, induces a back electromotive force (EMF) in opposition to . In accordance with Faraday's law of induction, the voltage induced across the primary winding is proportional to the rate of change of flux:

     and

where
  and  are the voltages across the primary winding and secondary winding,
  and  are the numbers of turns in the primary winding and secondary winding,
  and  are the derivatives of the flux with respect to time of the primary and secondary windings.

Saying that the primary and secondary windings are perfectly coupled is equivalent to saying that . Substituting and solving for the voltages shows that:

where
  and  are voltages across primary  and secondary,
  and  are the numbers of turns in the primary  and secondary , respectively.

Hence in an idéal transformer, the ratio of the primary and secondary voltages is equal to the ratio of the number of turns in their windings, or alternatively, the voltage per turn is the same for both windings.  The ratio of the currents in the primary and secondary circuits is inversely proportional to the turns ratio. This léads to the most common use of the transformer: to convert electrical energy at one voltage to energy at a different voltage by méans of windings with different numbers of turns. In a practical transformer, the higher-voltage winding will have more turns, of smaller conductor cross-section, than the lower-voltage windings.

The EMF in the secondary winding, if connected to an electrical circuit, will cause current to flow in the secondary circuit. The  MMF produced by current in the secondary opposes the MMF of the primary and so tends to cancel the flux in the core. Since the reduced flux reduces the EMF induced in the primary winding, incréased current flows in the primary circuit. The resulting incréase in MMF due to the primary current offsets the effect of the opposing  secondary MMF.  In this way, the electrical energy fed into the primary winding is delivered to the secondary winding. Also because of this, the flux density will always stay the same as long as the primary voltage is stéady.

For example, suppose a power of 50 watts is supplied to a resistive load from a transformer with a turns ratio of 25:2.

 P = EI (power = electromotive force × current)
 50 W = 2 V × 25 A in the primary circuit if the load is a resistive load. (See note 1)

 Now with transformer change:
 50 W = 25 V × 2 A in the secondary circuit.

Analisis trafo bulak-balik
This tréats the windings as a pair of mutually coupled coils with both primary and secondary windings passing currents. In an ideal transformer the primary MMF must equal the secondary MMF, and since these are in opposite directions, they oppose so that there is no overall resultant flux in the core. That this is so can be seen by réalising that any unopposed primary emf would créate a large primary current and therefore a large flux in the core due to the primary winding. However, this large flux would necessarily cause a large current to flow in the secondary circuit and this current must créate an opposing flux that effectively cancels the initiating primary flux.

In a non-idéal transformer, the resultant flux in the core is that needed to magnetise the core. This is called the magnetising flux.

Arus saarah

Transformers should not be driven with DC nor, generally, have any DC component present at the input. Relatively small amounts of direct current can cause core saturation and thus prevent proper operation. Also, since a DC voltage source would not give a time-varying flux in the core, no induced counter-EMF would be generated and so current flow into the transformer would be limited only by the series resistance of the windings. In this situation, the transformer would héat until the transformer either réaches thermal equilibrium or is destroyed. This principle is actually exploited when large power transformers must be dried (have condensation and other water removed from their windings) — they are simply héated using DC.

For the same réason, transformers should generally not have DC components present in their output windings. A notable violation of this rule occurs with half-wave rectifiers, where the transformer winding must also carry the DC load current; these circuits are usually used in low-power applications because of this.  Full-wave rectifiers, by comparison, do not require direct current to flow through the transformer and so are capable of much higher power levels.

Persamaan emf unifersal
If the flux in the core is sinusoidal, the relationship for either winding between its number of turns, voltage, magnetic flux density and core cross-sectional aréa is given by the universal emf equation (from Faraday's law):

where
  is the sinusoidal rms or root mean square voltage of the winding,
  is the frequency in hertz,
  is the number of turns of wire on the winding,
  is the cross-sectional aréa of the core in square metres
  is the péak magnetic flux density in teslas
  is the power in volt amperes or watts,
Other consistent systems of units can be used with the appropriate conversions in the equation.

Panimuan

Those credited with the invention of the transformer include:

 Michael Faraday, who invented an 'induction ring' on August 29 1831. This was the first transformer, although Faraday used it only to demonstrate the principle of electromagnetic induction and did not foresee the use to which it would eventually be put.
 Lucien Gaulard and John Dixon Gibbs, who first exhibited a device called a 'secondary generator' in London in 1881 and then sold the idéa to American company Westinghouse. This may have been the first practical power transformer. They also exhibited the invention in Turin in 1884, where it was adopted for an electric lighting system. Their éarly devices used an open iron core, which was soon abandoned in favour of a more efficient circular core with a closed magnetic path.

 William Stanley, an engineer for Westinghouse, who built the first practical device in 1885 after Géorge Westinghouse bought Gaulard and Gibbs' patents. The core was made from interlocking E-shaped iron plates. This design was first used commercially in 1886.
 Hungarian engineers Károly Zipernowsky, Ottó Bláthy and Miksa Déri at the Ganz company in Budapest in 1885, who créated the efficient "ZBD" modél based on the design by Gaulard and Gibbs.
 Nikola Tesla in 1891 invented the Tesla coil, which is a high-voltage, air-core, dual-tuned resonant transformer for generating very high voltages at high frequency.

Many others have patents on transformers.

Pertimbangan parktis

Klasifikasi
Transformers are adapted to numerous engineering applications and may be classified in many ways:
 By power level (from fraction of a volt-ampere(VA) to over a thousand MVA),
 By application (power supply, impedance matching, circuit isolation),
 By frequency range (power, audio, radio frequency(RF))
 By voltage class (a few volts to about 750 kilovolts)
 By cooling type (air cooled, oil filled, fan cooled, water cooled, etc.)
 By purpose (distribution, rectifier, arc furnace, amplifier output, etc.).
 By ratio of the number of turns in the coils
 Step-up
 The secondary has more turns than the primary.
 Step-down
 The secondary has fewer turns than the primary.
 Isolating
 Intended to transform from one voltage to the same voltage. The two coils have approximately equal numbers of turns, although often there is a slight difference in the number of turns, in order to compensate for losses (otherwise the output voltage would be a little less than, rather than the same as, the input voltage).
 Variable
 The primary and secondary have an adjustable number of turns which can be selected without reconnecting the transformer.

Lambang sirkuit
Standard symbols

Karugian
An idéal transformer would have no losses, and would therefore be 100% efficient. In practice, energy is dissipated due both to the resistance of the windings known as copper loss or I2 R loss, and to magnetic effects primarily attributable to the core (known as iron loss méasured in watts per pound). Transformers are, in general, highly efficient. Large power transformers (over 50 MVA) may attain an efficiency as high as 99.75%. Small transformers, such as a plug-in "power brick" used to power small consumer electronics, may be less than 85% efficient.

Transformer losses arise from:
 Winding resistance
Current flowing through the windings causes resistive héating of the conductors (I2 R loss). At higher frequencies, skin effect and proximity effect créate additional winding resistance and losses.
 Eddy currents
Induced eddy currents circulate within the core, causing resistive héating. Silicon is added to the steel to help in controlling eddy currents. Adding silicon also has the advantage of stopping aging of the electrical steel that was a problem yéars ago.
 Hysteresis losses
éach time the magnetic field is reversed, a small amount of energy is lost to hysteresis within the magnetic core. The amount of hysteresis is a function of the particular core material.
 Magnetostriction
Magnetic flux in the core causes it to physically expand and contract slightly with the alternating magnetic field, an effect known as magnetostriction. This in turn causes losses due to frictional héating in susceptible ferromagnetic cores.
 Mechanical losses
In addition to magnetostriction, the alternating magnetic field causes fluctuating electromagnetic forces between the primary and secondary windings. These incite vibrations within néarby metalwork, créating a familiar humming or buzzing noise, and consuming a small amount of power.
 Stray losses
Not all the magnetic field produced by the primary is intercepted by the secondary. A portion of the leakage flux may induce eddy currents within néarby conductive objects, such as the transformer's support structure, and be converted to héat.
 Cooling system
Large power transformers may be equipped with cooling fans, oil pumps or water-cooled héat exchangers designed to remove the héat caused by copper and iron losses. The power used to operate the cooling system is typically considered part of the losses of the transformer.

Operasi dina frékuénsi nu béda
The equation shows that the EMF of a transformer at a given flux density incréases with frequency. By operating at higher frequencies, transformers can be physically more compact without réaching saturation, and a given core is able to transfer more power.   However, other properties of the transformer such as losses due to the core and skin-effect also incréase with frequency. Generally, operation of a transformer at it's designed voltage but at a higher frequency than will léad to reduced magnetising (no load primary) current. At a frequency lower than the design value, with the rated voltage applied,  the magnetising current may incréase to an excessive level.

Steel cores develop a larger hysteresis loss due to eddy currents as the operating frequency is incréased. Ferrite, or thinner steel laminations for the core are typically used for frequencies above 1 kHz. The thinner steel laminations serve to reduce the eddy currents. Some types of very thin steel laminations can be ran up to 10 kHz or more. Ferrite is used in higher frequencies up to the VHF band and beyond. Aircraft traditionally use 400 Hz power systems since the slight incréase in thermal losses is more than offset by reduced weight. Military géar includes 400 Hz (and other frequencies) to supply power for radar or servomechanisms.

Flyback transformers are built using ferrite cores.  They supply high voltage to the CRTs at the frequency of the horizontal oscillator. In the case of television sets, this is about 15.7 kHz. It may be as high as 75 – 120 kHz for high-resolution computer monitors.

Switching power supply transformers usually operate between 50–1000 kHz. The tiny cores found in wristwatch backlight power supplies produce audible sound (about 1 kHz).

Operation of a power transformer at other than its design frequency may require assessment of voltages, losses, and cooling to establish if safe operation is practical. For example, transformers at hydroelectric generating stations may be equipped with over-excitation protection, so-called "volts per hertz" protection relays, to protect the transformer from overvoltage at higher-than-rated frequency which may occur if a generator loses its connected load.

Construksi

Inti

Inti waja

Transformers for use at power or audio frequencies have cores made of many thin laminations of silicon steel. By concentrating the magnetic flux, more of it is usefully linked by both primary and secondary windings. Since the steel core is conductive, it, too, has currents induced in it by the changing magnetic flux. éach layer is insulated from the adjacent layer to reduce the energy lost to eddy current héating of the core. The thin laminations are used to reduce the eddy currents, and the insulation is used to keep the laminations from acting as a solid piece of steel. The thinner the laminations, the lower the eddy currents, and the lower the losses. Very thin laminations are generally used on high frequency transformers. The cost goes up when using thinner laminations mainly over the labor in stacking them. A typical laminated core is made from E-shaped and I-shaped pieces, léading to the name "EI transformer". There is other types such as the C-core or "cut core" transformer. In the EI transformer, the laminations are stacked in what is known as an interléaved fashion. This is where the E and I pieces are staggered while stacking to reduce any gap. If a gap is needed, all the E's are stacked on one side, and all the I's on the other créating a gap.

The cut core or C-core is made by winding a silicon steel strip around a rectangular form. After the required thickness is achieved, it is removed from the form and the laminations are bonded together. It is then cut in two forming two C shapes. The faces of the cuts are then ground smooth so they fit very tight with a very small gap to reduce losses. To use a C-core, a coil is wound which is then placed over a leg of one half of the core. The core is then assembled by placing the two C halves together, and holding them closed by a steel strap. In this type of core, the coil will be on one leg, and the other is bare. There is shell type cores available which are similar to the EI cores.

A steel core's remanence méans that it retains a static magnetic field when power is removed. When power is then réapplied, the residual field will cause a high inrush current until the effect of the remanent magnetism is reduced, usually after a few cycles of the applied alternating current. Overcurrent protection devices such as fuses must be selected to allow this harmless inrush to pass. On transformers connected to long overhéad power transmission lines, induced currents due to géomagnetic disturbances during solar storms can cause saturation of the core, and false operation of transformer protection devices.

Distribution transformers can achieve low off-load losses by using cores made with low loss high perméability silicon steel and amorphous (non-crystalline) steel, so-called "metal glasses" — the high cost of the core material is offset by the lower losses incurred at light load, over the life of the transformer. In order to maintain good voltage regulation, distribution transformers are designed to have very low leakage inductance.

Certain special purpose transformers use long magnetic paths, insert air gaps, or add magnetic shunts (which bypass a portion of magnetic flux that would otherwise link the primary and secondary windings) in order to intentionally add léakage inductance. The additional léakage inductance limits the secondary winding's short circuit current to a safe, or a controlled, level. This technique is used to stabilize the output current for loads that exhibit negative resistance such as electric arcs, mercury vapor lamps, and neon signs, or safely handle loads that may become periodically short-circuited such as electric arc welders. Gaps are also used to keep a transformer from saturating, especially audio transformers which have a DC component added.

Inti padet
Powdered iron cores are used in circuits (such as switch-mode power supplies) that operate above mains frequencies and up to a few tens of kilohertz. These materials combine high magnetic permeability with high bulk electrical resistivity.

At even higher, radio-frequencies (RF), other types of cores made from non-conductive magnetic ceramic materials, called ferrites, are common. Some RF transformers also have movéable cores (sometimes called slugs) which allow adjustment of the coupling coefficient (and bandwidth) of tuned radio-frequency circuits.

Inti udara
High-frequency transformers may also use air cores. These eliminate the loss due to hysteresis in the core material. Such transformers maintain high coupling efficiency (low stray field loss) by overlapping the primary and secondary windings.

Inti toroid

Toroidal transformers are built around a ring-shaped core, which is made from a long strip of silicon steel or permalloy wound into a coil, from powdered iron, or ferrite, depending on operating frequency. The strip construction ensures that the grain boundaries are optimally aligned, improving the transformer's efficiency by reducing the core's reluctance. The closed ring shape eliminates air gaps inherent in the construction of an EI core. The cross-section of the ring is usually square or rectangular, but more expensive cores with circular cross-sections are also available.  The primary and secondary coils are often wound concentrically to cover the entire surface of the core.  This minimises the length of wire needed, and also provides screening to minimize the core's magnetic field from generating electromagnetic interference.

Ferrite toroid cores are used at higher frequencies, typically between a few tens of kilohertz to a megahertz, to reduce losses, physical size, and weight of switch-mode power supplies.

Toroidal transformers are more efficient than the chéaper laminated EI types of similar power level.  Other advantages, compared to EI types, include smaller size (about half), lower weight (about half), less mechanical hum (making them superior in audio amplifiers), lower exterior magnetic field (about one tenth), low off-load losses (making them more efficient in standby circuits), single-bolt mounting, and more choice of shapes. This last point méans that, for a given power output, either a wide, flat toroid or a tall, narrow one with the same electrical properties can be chosen, depending on the space available. The main disadvantages are higher cost and limited size.

A drawback of toroidal transformer construction is the higher cost of windings. As a consequence, toroidal transformers are uncommon above ratings of a few kVA. Small distribution transformers may achieve some of the benefits of a toroidal core by splitting it and forcing it open, then inserting a bobbin containing primary and secondary windings.

When fitting a toroidal transformer, it is important to avoid making an unintentional short-circuit through the core. This can happen if the steel mounting bolt in the middle of the core is allowed to touch metalwork at both ends, making a loop of conductive material which passes through the hole in the toroid.  Such a loop could result in a dangerously large current flowing in the bolt.

Beulitan
The wire of the adjacent turns in a coil, and in the different windings, must be electrically insulated from éach other. The wire used is generally magnet wire. Magnet wire is a copper wire with a coating of varnish or some other synthetic coating. Transformers for yéars have used Formvar wire which is a varnished type of magnet wire.

The conducting material used for the winding depends upon the application. Small power and signal transformers are wound with solid copper wire, insulated usually with enamel, and sometimes additional insulation. Larger power transformers may be wound with wire, copper, or aluminum rectangular conductors. Strip conductors are used for very héavy currents. High frequency transformers operating in the tens to hundreds of kilohertz will have windings made of Litz wire to minimize the skin effect losses in the conductors. Large power transformers use multiple-stranded conductors as well, since even at low power frequencies non-uniform distribution of current would otherwise exist in high-current windings. éach strand is insulated from the other, and the strands are arranged so that at certain points in the winding, or throughout the whole winding, éach portion occupies different relative positions in the complete conductor. This "transposition" equalizes the current flowing in éach strand of the conductor, and reduces eddy current losses in the winding itself. The stranded conductor is also more flexible than a solid conductor of similar size. (see reference (1) below)

For signal transformers, the windings may be arranged in a way to minimise léakage inductance and stray capacitance to improve high-frequency response. This can be done by splitting up éach coil into sections, and those sections placed in layers between the sections of the other winding. This is known as a stacked type or interléaved winding.

Windings on both the primary and secondary of power transformers may have external connections (called taps) to intermediate points on the winding to allow adjustment of the voltage ratio. Taps may be connected to an automatic, on-load tap changer type of switchgear for voltage regulation of distribution circuits. Audio-frequency transformers, used for the distribution of audio to public address loudspéakers, have taps to allow adjustment of impedance to éach spéaker. A center-tapped transformer is often used in the output stage of an audio power amplifier in a push-pull type circuit. Modulation transformers in AM transmitters are very similar. Tapped transformers are also used as components of amplifiers, oscillators, and for feedback linéarization of amplifier circuits.

Isolasi
The turns of the windings must be insulated from éach other to ensure that the current travels through the entire winding.  The potential difference between adjacent turns is usually small, so that enamel insulation is usually sufficient for small power transformers. In larger transformers additional layers of insulation are used.

The transformer may also be immersed in transformer oil that provides further to the insulation. The oil is primarily used to cool the transformer. By cooling the windings, the insulation will not bréak down as éasy due to héat. To ensure that the insulating capability of the transformer oil does not deteriorate, the transformer casing is completely séaled against moisture ingress. Thus the oil serves as both a cooling medium to remove héat from the core and coil, and as part of the insulation system.

Certain power transformers have the windings protected by a layer of epoxy resin. This produces transformers suitable for damp or dirty environments, but at incréased manufacturing cost.

Shielding
Where transformers are intended for minimum electrostatic coupling between primary and secondary circuits, an electrostatic shield can be placed between windings to reduce the capacitance between primary and secondary windings.  The shield may be a single layer of metal foil, insulated where it overlaps to prevent it acting as a shorted turn, or a single layer winding between primary and secondary. The shield is connected to éarth ground.

Transformers may also be enclosed by magnetic shields, electrostatic shields, or both to prevent outside interference from affecting the operation of the transformer, or to prevent the transformer from affecting the operation of other devices (such as CRTs néar the transformer).

Paniis

Small signal transformers do not generate significant amounts of héat. Power transformers rated up to a few kilowatts rely on natural convective air cooling. Specific provision must be made for cooling of high-power transformers. Transformers handling higher power, or having a high duty cycle can be fan-cooled.

Some dry transformers are enclosed in pressurized tanks and are cooled by nitrogen or sulfur hexafluoride gas.

The windings of high-power or high-voltage transformers are immersed in transformer oil — a highly-refined mineral oil, that is stable at high temperatures. Large transformers to be used indoors must use a non-flammable liquid. Formerly, polychlorinated biphenyl (PCB) was used as it was not a fire hazard in indoor power transformers and it is highly stable. Due to the stability and toxic effects of PCB byproducts, and its environmental accumulation, it is no longer permitted in new equipment. Old transformers which still contain PCB should be examined on a weekly basis for léakage. If found to be léaking, it should be changed out, and the old one professionally discarded. Today, nontoxic, stable silicone-based oils, or fluorinated hydrocarbons may be used where the expense of a fire-resistant liquid offsets additional building cost for a transformer vault. Other less-flammable fluids such as canola oil may be used but all fire resistant fluids have some drawbacks in performance, cost, or toxicity compared with mineral oil.

The oil cools the transformer, and provides part of the electrical insulation between internal live parts. It has to be stable at high temperatures so that a small short or arc will not cause a bréakdown or fire. The oil-filled tank may have radiators through which the oil circulates by natural convection. Very large or high-power transformers (with capacities of millions of watts) may have cooling fans, oil pumps and even oil to water heat exchangers. Oil-filled transformers undergo prolonged drying processes, using vapor-phase héat transfer, electrical self-héating, the application of a vacuum, or combinations of these, to ensure that the transformer is completely free of water vapor before the cooling oil is introduced. This helps prevent electrical bréakdown under load.

Oil-filled power transformers may be equipped with Buchholz relays which are safety devices that sense gas build-up inside the transformer (a side effect of an electric arc inside the windings), and thus switches off the transformer.

Experimental power transformers in the 2 MVA range have been built with superconducting windings which eliminates the copper losses, but not the core steel loss. These are cooled by liquid nitrogen or helium.

Terminal
Very small transformers will have wire léads connected directly to the ends of the coils, and brought out to the base of the unit for circuit connections. Larger transformers may have héavy bolted terminals, bus bars or high-voltage insulated bushings made of polymers or porcelain.  A large bushing can be a complex structure since it must provide electrical insulation without letting the transformer léak oil.

Lampiran
Small transformers often have no enclosure. Transformers may have a shield enclosure, as described above. Larger units  may be enclosed to prevent contact with live parts, and to contain the cooling medium (oil or pressurized gas).

Tipe trafo

Autotrafo

An autotransformer has only a single winding, which is tapped at some point along the winding. AC or pulsed voltage is applied across a portion of the winding, and a higher (or lower) voltage is produced across another portion of the same winding. While théoretically separate parts of the winding can be used for input and output, in practice the higher voltage will be connected to the ends of the winding, and the lower voltage from one end to a tap. For example, a transformer with a tap at the center of the winding can be used with 230 volts across the entire winding, and 115 volts between one end and the tap. It can be connected to a 230 volt supply to drive 115 volt equipment, or reversed to drive 230 volt equipment from 115 volts. As the same winding is used for input and output, the flux in the core is partially cancelled, and a smaller core can be used. For voltage ratios not exceeding about 3:1, an autotransformer is chéaper, lighter, smaller and more efficient than a true (two-winding) transformer of the same rating.

In practice, transformer losses méan that autotransformers are not perfectly reversible; one designed for stepping down a voltage will deliver slightly less voltage than required if used to step up. The difference is usually slight enough to allow reversal where the actual voltage level is not critical.

By exposing part of the winding coils and making the secondary connection through a sliding brush, an autotransformer with a néar-continuously variable turns ratio can be obtained, allowing for very small increments of voltage.

Trafo polifase
For three-phase power, three separate single-phase transformers can be used, or all three phases can be connected to a single polyphase transformer. The three primary windings are connected together and the three secondary windings are connected together. The most common connections are Y-Δ, Δ-Y, Δ-Δ and Y-Y. A vector group indicates the configuration of the windings and the phase angle difference between them. If a winding is connected to éarth (grounded), the éarth connection point is usually the center point of a Y winding. If the secondary is a Δ winding, the ground may be connected to a center tap on one winding (high leg delta) or one phase may be grounded (corner grounded delta). There are many possible configurations that may involve more or fewer than six windings and various tap connections.

Trafo résonansi
A resonant transformer is one that operates at the resonant frequency of one or more of its coils and, usually, an external capacitor.  The resonant coil, usually the secondary, acts as an inductor, and is connected in series with a capacitor.  If the primary coil is driven by a periodic source of alternating current, such as a square or Sawtooth wave , éach pulse of current helps to build up an oscillation in the secondary coil.  Due to resonance, a very high voltage can develop across the secondary, until it is limited by some process such as electrical breakdown.  These devices are therefore used to generate high alternating voltages.  The current available from this type of coil can be much larger than that from electrostatic machines such as the Van de Graaff generator and Wimshurst machine. They also run at a higher operating temperature than standard units.

Examples:
 Tesla coil
 Oudin coil (or Oudin resonator; named after its inventor Paul Oudin)
 D'Arsonval apparatus
 Ignition coil or induction coil used in the ignition system of a petrol engine
 Flyback transformer of a CRT television set or vidéo monitor.
 Electrical breakdown and insulation testing of high voltage equipment and cables

Other applications of resonant transformers are as coupling between stages of a superheterodyne receiver, where the selectivity of the receiver is provided by the tuned transformers of the intermediate-frequency amplifiers.

A voltage regulating transformer uses a resonant winding and allows part of the core to go into saturation on éach cycle of the alternating current. This effect stabilizes the output of the regulating transformer, which can be used for equipment that is sensitive to variations of the supply voltage. Saturating transformers provide a simple rugged method to stabilize an ac power supply. However, due to the hysteresis losses accompanying this type of operation, efficiency is low.

Trafo instrumén

Trafo arus
A current transformer is a type of "instrument transformer" that is designed to provide a current in its secondary which is accurately proportional to the current flowing in its primary.

Current transformers are commonly used in métering and protective relaying to facilitate the méasurement of large currents and isolation of high voltage systems which would be difficult to méasure more directly.

Current transformers are often constructed by passing a single primary turn (either an insulated cable or an uninsulated conductor (copper or aluminum are typical in electric utility applications) through a well-insulated toroidal core wrapped with many turns of wire. Current transformers (CTs) are used extensively in the electrical power industry for monitoring of the power grid.  The CT is described by its current ratio from primary to secondary.  Common secondaries are 1 or 5 amperes.  The secondary winding can be single ratio or multi ratio, with five taps being common for multi ratio CTs. Typically, the secondary connection points are labeled as X1, X2 and so on. The multi ratio CTs are typically used for current matching in current differential protective relaying applications. Often, multiple CTs will be installed as a "stack" for various uses (for example, protection devices and revenue métering may use separate CTs). For a three-stacked CT application, the secondary winding connection points are typically labeled Xn, Yn, Zn.

Specially constructed wideband current transformers are also used (usually with an oscilloscope) to méasure waveforms of high frequency or pulsed currents. One type of specially constructed wideband transformer provides a voltage output that is proportional to the méasured current. Another type (called a Rogowski coil) requires an external integrator in order to provide a voltage output that is proportional to the méasured current.

Care must be taken that the secondary of a current transformer is not disconnected from its load while current is flowing in the primary, as this will produce a dangerously high voltage across the open secondary.

Trafo tegangan
Voltage transformers (or potential transformers) are another type of instrument transformer, used for métering and protection in high-voltage circuits. They are designed to present negligible load to the supply being méasured and to have a precise voltage ratio to accurately step down  high voltages so that métering and protective relay equipment can be operated at a lower potential. Typically the secondary of a voltage transformer is rated for 69 or 120 Volts at rated primary voltage, to match the input ratings of protection relays.

The transformer winding high-voltage connection points are typically labelled as H1, H2 (sometimes H0 if it is internally grounded) and X1, X2, and sometimes an X3 tap may be present. Sometimes a second isolated winding (Y1, Y2, Y3) may also be available on the same voltage transformer.  The high side (primary) may be connected phase to ground or phase to phase. The low side (secondary) is usually phase to ground.

The terminal identifications (H1, X1, Y1, etc.) are often referred to as polarity. This applies to current transformers as well. At any instant terminals with the same suffix numeral have the same polarity and phase. Correct identification of terminals and wiring is important for proper operation of métering and protection relays.

Trafo pulse
A pulse transformer is a transformer that is optimised for transmitting rectangular electrical pulses (that is, pulses with fast rise and fall times and a constant amplitude).  Small versions called signal types are used in digital logic and telecommunications circuits, often for matching logic drivers to transmission lines.  Medium-sized power versions are used in power-control circuits such as camera flash controllers.  Larger power versions are used in the electrical power distribution industry to interface low-voltage control circuitry to the high-voltage gates of power semiconductors. Special high voltage pulse transformers are also used to generate high power pulses for radar, particle accelerators, or other pulsed power applications.

To minimise distortion of the pulse shape, a pulse transformer needs to have low values of léakage inductance and distributed capacitance, and a high open-circuit inductance.  In power-type pulse transformers, a low coupling capacitance (between the primary and secondary) is important to protect the circuitry on the primary side from high-powered transients créated by the load.  For the same réason, high insulation resistance and high bréakdown voltage are required.  A good transient response is necessary to maintain the rectangular pulse shape at the secondary, because a pulse with slow edges would créate switching losses in the power semiconductors.

The product of the péak pulse voltage and the duration of the pulse (or more accurately, the voltage-time integral) is often used to characterise pulse transformers.  Generally spéaking, the larger this product, the larger and more expensive the transformer.

Trafo RF (trafo jalur transmisi)
For radio frequency use, transformers are sometimes made from configurations of transmission line, sometimes bifilar or coaxial cable, wound around ferrite or other types of core. This style of transformer gives an extremely wide bandwidth but only a limited number of ratios (such as 1:9, 1:4 or 1:2) can be achieved with this technique.

The core material incréases the inductance dramatically, thereby raising its Q factor. The cores of such transformers help improve performance at the lower frequency end of the band.
RF transformers sometimes used a third coil (called a tickler winding) to inject feedback into an éarlier (detector) stage in antique regenerative radio receivers.

Baluns
Baluns are transformers designed specifially to connect between balanced and unbalanced circuits. These are sometimes made from configurations of transmission line and sometimes bifilar or coaxial cable and are similar to transmission line transformers in construction and operation.

Trafo audio

Audio transformers are usually the factor which limit sound quality; electronic circuits with wide frequency response and low distortion are relatively simple to design.

Transformers are also used in DI boxes to convert impedance from high-impedance instruments (for example, bass guitars) to enable them to be connected to a microphone input on the mixing console.

A particularly critical component is the output transformer of an audio power amplifier. Valve circuits for quality reproduction have long been produced with no other (inter-stage) audio transformers, but an output transformer is needed to couple the relatively high impedance (up to a few hundred ohms depending upon configutation) of the output valve(s) to the low impedance of a loudspeaker. (The valves can deliver a low current at a high voltage; the spéakers require high current at low voltage.) Solid-state power amplifiers may need no output transformer at all.

For good low-frequency response a relatively large iron core is required; high power handling incréases the required core size. Good high-frequency response requires carefully designed and implemented windings without excessive leakage inductance or stray capacitance. All this makes for an expensive component.

Output transformerless audio power valve amplifiers are possible, but were rarely used due to other disadvantages.

éarly transistor audio power amplifiers often had output transformers, but they were eliminated as designers discovered how to design amplifiers without them.

Trafo speaker

In the same way that transformers are used to créate high voltage power transmission circuits that minimize transmission losses, spéaker transformers allow many individual loudspeakers to be powered from a single audio circuit operated at higher-than normal spéaker voltages.  This application is common in public address (e.g., Tannoy) applications. Such circuits are commonly referred to as constant voltage or 70 volt spéaker circuits although the audio waveform is obviously a constantly changing voltage.

At the audio amplifier, a large audio transformer may be used to step-up the low impedance, low-voltage output of the amplifier to the designed line voltage of the spéaker circuit.  Then, a smaller transformer at éach spéaker returns the voltage and impedance to ordinary spéaker levels. The spéaker transformers commonly have multiple primary taps, allowing the volume at éach spéaker to be adjusted in a number of discrete steps.

Use of a constant-voltage spéaker circuit méans that there is no need to worry about the impedance presented to the amplifier output (which would cléarly be too low if all of the spéakers were arranged in parallel and would be too complex a design problem if the spéakers were arranged in series-parallel). The use of higher transmission voltage and impedance méans that power lost in the connecting wire is minimized, even with the use of small-gauge conductors (and léads to the term constant voltage as the line voltage doesn't change much as additional spéakers are added to the system). Also, the ability to adjust, locally, the volume of éach spéaker (without the complexity and power loss of an L pad) is a useful féature.

Kagunaan trafo
 For supplying power from an alternating current power grid to equipment which uses a different voltage.
 Electric power transmission over long distances.
 Large, specially constructed power transformers are used for electric arc furnaces used in steelmaking.
 Rotating transformers are designed so that one winding turns while the other remains stationary. A common use was the vidéo héad system as used in VHS and Beta vidéo tape players. These can pass power or radio signals from a stationary mounting to a rotating mechanism, or radar antenna.
 Sliding transformers can pass power or signals from a stationary mounting to a moving part such as a machine tool héad.
 A transformer-like device is used for position méasurement.  See linear variable differential transformer.
 Some rotary transformers are used to couple signals between two parts which rotate in relation to éach other.
 Other rotary transformers are precisely constructed in order to méasure distances or angles. Usually they have a single primary and two or more secondaries, and electronic circuits méasure the different amplitudes of the currents in the secondaries. See synchro and resolver.
 Small transformers are often used internally to couple different stages of  radio receivers and audio amplifiers.
 Transformers may be used as external accessories for impedance matching; for example to match a microphone to an amplifier.
 Balanced-to-unbalanced conversion.  A special type of transformer called a balun is used in radio and audio circuits to convert between balanced linecircuits and unbalanced transmission lines such as antenna downléads.

Tempo ogé

 Main : Distributed generation, Electronic power supply, Electronics, Inductor, Pickup, Electrical network, Electricity distribution, Wet transformer, List of electronics topics, Electronic transformer, Load profile, Transformer effect
 Circuits: Clamp meter, Repeating coil, Inverter (electrical), Ignition system, Electricity generation, Linear variable differential transformer, Neon signage, Regulator, Electrical substation, Switched-mode power supply, Technological applications of superconductivity, Tesla coil, Transducer
 Electromagnetism: Alternating current, Electric power, Electric power transmission, Electromagnetic induction, Equivalent series resistance, High-voltage direct current, Impedance matching, Inductive coupling, Potential difference, Skin effect, Leakage inductance, Superconductivity
 People: Ottó Bláthy, Miksa Déri, John Ambrose Fleming, Otto A. Knopp, William Stanley, Nikola Tesla, Milan Vidmar, George Westinghouse, Károly Zipernowsky
 Other: DI unit, Polychlorinated biphenyl, Stafford, Timeline of invention, War of Currents, World's Columbian Exposition

Tumbu luar
 Transformer Learning Centre Learn more about Transformers and how they work
 Inside Transformers from Denver University
 Understanding Transformers: Characteristics and Limitations from Conformity Magazine
 3 Phase Transformer Information and Construction — The 3 Phase Power Resource Site
 DMOZ: Business: Electronics and Electrical: Substation and Transmission   Transformers for the Utility sector
 Electronic Transformers types and structures
 J.Edwards and T.K Saha, Power flow in transformers via the Poynting vector (PDF)
 A transformer explodes

Référénsi

 Kinds of Transformers
 Electrical Engineering Fundamentals by J P Néal dept of Elec Eng, University of illinois. publ McGraw Hill 1960 Library of Congress No 59-13210. Sect 7-9 on mutual inductance , p301,

Dicutat tina

Éléktronika

Trafo


In Norse meethologie, Freyja (Auld Norse the "Lady") is a goddess associatit wi luve, brawnie, fertility, gowd, seiðr, war, an daith. Freyja is the awner o the necklace Brísingamen, rides a chariot pulled bi twa cats, awns the boar Hildisvíni, possesses a cloak o falcon feathers, an, bi her husband Óðr, is the mither o twa dochters, Hnoss an Gersemi. Alang wi her brither Freyr (Auld Norse the "Lord"), her faither Njörðr, an her mither (Njörðr's sister, unnamed in soorces), she is a member o the Vanir. Stemmin frae Auld Norse Freyja, modren forms o the name include Freya, Frejya, Freyia, Frøya, Frøjya, an Freia.

Freyja rules ower her heivenly efterlife field Fólkvangr an thare receives hauf o those that dee in battle, whareas the ither hauf go tae the god Odin's haw, Valhalla. Athin Fólkvangr is her haw, Sessrúmnir. Freyja assists ither deities bi allouin thaim tae uise her feathered cloak, is invokit in matters o fertility an luve, an is frequently soucht efter bi pouerful jötnar who wish tae mak her thair wife. Freyja's husband, the god Óðr, is frequently absent. She cries tears o reid gowd for him, an searches for him unner assumit names. Freyja haes numerous names, includin Gefn, Hörn, Mardöll, Sýr, Valfreyja, an Vanadís.

Freyja is attestit in the Poetic Edda, compiled in the 13t century frae earlier tradeetional soorces; in the Prose Edda an Heimskringla, baith written bi Snorri Sturluson in the 13t century; in several Sagas o Icelanders; in the short story Sörla þáttr; in the poetry o skalds; an intae the modren age in Scandinavie fowklear, as well as the name for Friday in mony Germanic leids.

Scholars hae theorisit aboot whether or no Freyja an the goddess Frigg ultimately stem frae a single goddess common amang the Germanic fowks; aboot her connection tae the valkyries, female battlefield chuisers o the slain; an her relation tae ither goddesses an figurs in Germanic meethologie, includin the thrice-burnt an thrice-reborn Gullveig/Heiðr, the goddesses Gefjon, Skaði, Þorgerðr Hölgabrúðr an Irpa, Menglöð, an the 1st century CE "Isis" o the Suebi. Freyja's name appears in numerous place names in Scandinavie, wi a heich concentration in soothren Swaden. Various plants in Scandinavie ance bore her name, but it wis replacit wi the name o the Virgin Mary durin the process o Christianisation. Landwart Scandinavies continued tae acknawledge Freyja as a supernatural figur intae the 19t century, an Freyja haes inspired various wirks o airt.

Etymologie
The name Freyja is in fact a teetle meanin "lady", frae Proto-Germanic *frawjōn, cognate wi Wast Frisie frou, Dutch vrouw, Law German Fro, Fru, German Frau.
The theonym Freyja wis sicweys an epithet in oreegin, replacin a personal name that is nou unattestit.
The connection wi an possible earlier identification o Freyja wi Frigg in the Proto-Germanic period (Frigg an Freyja oreegin hypothesis) is a matter o scholarly debate.

Lik the name o the group o gods tae which Freyja belangs, the Vanir, the name Freyja is no attestit ootside o Scandinavie, as opposed tae the name o the goddess Frigg, who is attestit as a goddess common amang aw Germanic fowks, an whose name is reconstructit as Proto-Germanic *Frijjō. Proof for the existence o a common Germanic goddess ance kent as *Fraujon daes no exist, but scholars hae commentit that this mey simply be due tae lack o evidence.

Regardin a Freyja-Frigg oreegin hypothesis, scholar Stephan Grundy comments that "the problem o whether Frigg or Freyja mey hae been a single goddess oreeginally is a difficult ane, made mair so bi the scantiness o pre-Viking Age references tae Germanic goddesses, an the diverse quality o the sources. The best that can be done is tae survey the arguments for an against their identity, an tae see hou well each can be supportit."

Bride o the Odr
Freyja marriet a god cried Óðr. She deeply loves her husband, but he aften went awa on lang journeys, an Freyja cried reid gowden tears for him. Her tears acome gowd an lammer whan thay fawl tae the Yird, tharefore gowd wis cried "Freyja's tears". Thay hae twa bonnie docters cried Hnoss an Gersemi.

Awner o the Gib-Cats an Brisingamen
Freyja aften rides in a chariot pulled bi big blue cats, or on a gowden battle boar. She is cried "The Fair One". In the meeths, thare wur three giants who wantit tae mairy Freyja, but thay wur aw killed bi Thor, the god o thunder.

Freyja haes a precious necklace cried Brisingamen (Jewelry o Fire). The god Loki ance stole this necklace, an Freyja haed tae ask the god Heimdall for help. Heimdall wan the fecht wi Loki an gae the necklace back tae Freyja. For this, Loki is cried "Thief o Brisingamen", an Heimdall is cried "Seeker o Brisingamen".

Whan Thrymr, the Keeng o the frost giants, tauld Loki tae ask Freyja tae acome his wife, the goddess wis sae angry that heiven wis shaken, an the necklace Brisingamen broke. The god Thor later borraeed the necklace an came tae the weddin, dressed up as Freyja. Thor killed Thrymr an aw his relatives.

Efter Ragnarok
In feenal battle o Ragnarok, Odin, Njord, an Freyr aw dee'd. Freyja alane remained amang the gods, an she continued the sacrifices.

Theories

Relation tae ither goddesses an figurs
In the Poetic Edda poem Völuspá, a figur bi the name o Gullveig is burnt three times yet is three times reborn. Efter her third rebirth, she is kent as Heiðr. This event is generally acceptit as precipitatin the Æsir-Vanir War. Stairtin wi scholar Gabriel Turville-Petre, scholars sic as Rudolf Simek, Andy Orchard, an John Lindow hae theorisit that Gullveig/Heiðr is the same figur as Freyja, an that her involvement wi the Æsir somehou led tae the events o the Æsir-Vanir War.

Ootside o theories connectin Freyja wi the goddess Frigg (see etymologie section abuin), some scholars, sic Hilda Ellis Davidson an Britt-Mari Näsström, hae theorisit that ither goddesses in Norse meethologie, sic as Gefjon, Gerðr, an Skaði, mey be forms o Freyja in different roles an/or ages.

Receiver o the slain
Freyja an her afterlife field Fólkvangr, whaur she receives hauf o the slain, haes been theorisit as connectit tae the valkyries. Scholar Britt-Mari Näsström pynts oot the description in Gylfaginning whaur it is said o Freyja that "whainiver she rides intae battle she taks hauf o the slain," an interprets Fólkvangr as "the field o the Warriors". Näsström notes that, juist lik Odin, Freyja receives slain heroes who hae dee'd on the battlefield, an that her hoose is Sessrumnir (which she translates as "filled wi mony seats"), a dwellin that Näsström posits likely fills the same function as Valhalla.

Modren influence
Freyja is mentioned in the first stanza ("it is cried auld Denmark an it is Freja's haw") o the ceevil naitional anthem o Denmark, Der er et yndigt land, written bi 19t century Dens poet Adam Gottlob Oehlenschläger in 1819. In addeetion, Oehlenschläger wrote a comedy enteetled Freyjas alter (1818) an a poem Freais sal featurin the goddess.

The 19t century German composer Richard Wagner's Der Ring des Nibelungen opera cycle featurs Freia, the goddess Freyja combined wi the aiple-bearin goddess Iðunn.

In late 19t century an early 20t century Northren Europe, Freyja wis the subject o numerous wirks o airt, includin Freyja bi H. E. Freund (statue, 1821–1822), Freja sökande sin make (pentin, 1852) bi Nils Blommér, Freyjas Aufnahme uner den Göttern (charcoal drawin, 1881) an Frigg; Freyja (drawin, 1883) bi Karl Ehrenberg, Freyja (1901) bi Carl Emil Doepler d. J., an Freyja and the Brisingamen bi J. Doyle Penrose (pentin, 1862–1932).

Vanadís, ane o Freyja's names, is the soorce o the name o the chemical element vanadium, sae namit acause o its mony coloured compoonds.

Notes

Freemit airtins
 Freya, wi the references tae her in auncient leeteratur

Ásynjur
Daith goddesses
Growthiness goddesses
Luve an lust goddesses
Cantrip goddesses
Vanir
War goddesses

Freyja


The Galatian War was a war between the Galatian Gauls and the Roman Republic supported by their allies Pergamum in 189 BC. The war was fought in Galatia in central Asia Minor, in present-day Turkey.

The Romans had just defeated the Seleucids in the Roman-Syrian War and had forced them to thereby sue for peace. Following their recently successful operation in Syria, the Romans then turned their attention towards the Gallic tribes of Galatia who had emigrated to Asia Minor almost 100 years prior to the ensuing military engagement. Gnaeus Manlius Vulso, the consul, excused the invasion by saying that it was in retaliation for the Galatians supplying troops to the Seleucids during the war. Vulso embarked on this campaign without the permission of the Roman Senate. Joined by Pergamum, the Romans marched inland and attacked the Galatians. They defeated the Galatians in a battle on Mount Olympus and followed up the victory by defeating a larger army near Ancyra (modern Ankara, Turkey).

These defeats forced the Galatians to sue for peace and the Romans returned to the coast of Asia Minor. However, when Manlius Vulso returned to Rome, he was charged with threatening the peace between the Seleucids and Rome. He was cleared and was granted a triumph by the Senate.

Prelude

In 191 BC, Antiochus the Great, the Emperor of the Seleucid Empire of Asia, invaded Greece. The Romans decided to intervene and they defeated the Seleucids at the Battle of Thermopylae. The defeat by Rome forced the Seleucids to retreat back to Asia Minor. The Romans followed them across the Aegean Sea and together with their allies, Pergamum, they decisively defeated the Seleucids at the Battle of Magnesia.

The Seleucids sued for peace and began settling it with Scipio Asiaticus. In spring, the new consul, Gnaeus Manlius Vulso, arrived to take control of the army from Scipio Asiaticus. He was sent to conclude the treaty that Scipio was arranging. However, he was not content with the task given to him and he started to plan a new war. He addressed the soldiers and congratulated them on their victory and then proposed a new war, against the Galatian Gauls of Asia Minor. The pretext he used for the invasion was that the Galatians had supplied soldiers to the Seleucid army at the Battle of Magnesia. The principal reason for the invasion was Manlius' desire to seize the wealth of the Galatians, who had become rich from plundering their neighbours, and to gain glory for himself.

This war was the first occasion on which a Roman general had started a war without the permission of the senate or the people. This was a dangerous precedent and this became an example for the future.

Manlius started his war preparation by summoning the Pergamese to help. However, the King of Pergamum, Eumenes II, was in Rome so his brother, Attalus, who was serving as regent, took command of the Pergamese army. He joined the Roman army a few days later with 1,000 infantry and 500 cavalry.

March inland
The combined Roman-Pergamese army started their march from Ephesus. They advanced inland passing Magnesia on the Maeander and into the territory of Alabanda where they were met by 1,000 infantry and 300 cavalry led by Attalus' brother. They then marched to Antiochia where they were met by Antiochus' son, Seleucus who offered corn as part of the treaty that was being concluded.

They marched inland through the upper Maeander valley and Pamphylia gathering levies from local princes and tyrants without much opposition. However, they then advanced into the territory of Cibrya, ruled by the tyrant Moagetes, known for his cruelty. When the Roman envoys reached the city, the tyrant begged them not to ravage the territory because he was a Roman ally and promised to give them fifteen talents. The envoys asked Moagetes to send envoys to Vulso's camp. Vulso met them as they approached the camp and addressed them as Polybius writes:

"Not only had Moagĕtes shown himself the most determined enemy of Rome, of all the princes in Asia, but had done his very best to overthrow their empire, and deserved punishment rather than friendship."

The envoys were terrified by his angry response and asked the consul to meet the tyrant for an interview to which Vulso agreed. The next day the tyrant emerged from the city and pleaded with Vulso to accept the fifteen talents. Vulso replied:

"If he did not pay five hundred talents, and be thankful that he was allowed to do so, he would not loot the country, but he would storm and sack the city."

The tyrant however, was able to persuade Vulso to reduce the price to 100 talents and promised to provide him with 1,000 medimni of wheat. Thus Moagĕtes managed to save his city. When the consul crossed the River Colobatus he was met by ambassadors from the town of Sinda in Pisidia. The ambassadors asked for assistance against the city of Termessus who had taken over all their country except for the capitol.

The consul agreed to the offer. He entered Termessian territory, allowing them to enter his alliance for fifty talents and for their withdrawal from Sindian territory. Vulso proceeded to seize the city of Cyrmasa in Pisidia and with it a large booty. He then took the city of Lysinoe before accepting a tribute of fifty talents and 20,000 medimni of barley  and wheat from the city of Sagalassus.

The consul reached the Rhotrine Springs and he was once again met by Seleucus. Seleucus took the injured and sick Romans with him to Apamea as well as supplying the Romans some guides. They marched for three days after departing from the springs and on the third day they arrived on the border with the Tolistobogii, one of the three Galatian tribes. The consul held an assembly and addressed his troops about the upcoming war. He then sent envoys to Eposognatus, chieftain of the Tectosagi, the only chieftain who was friendly with Pergamum. The envoys returned and replied that the chieftain of the Tectosagi begged the Romans not to invade his territory. He also claimed that he would attempt to force the submission of the other chieftains.

The army marched deeper inland and pitched camp near a Galatian stronghold called Cuballum. While they were there, the Galatian cavalry attacked the army's advance guard and caused significant casualties before the Roman cavalry counter-attacked and drove back the Galatians with heavy losses. The consul, knowing that he was in reach of the enemy, decided to move forward more cautiously.

Battle of Mount Olympus

The Romans and the Pergamenese arrived at the city of Gordium and found it deserted. As they camped there they were met by a messenger sent by Eposognatus. The messenger reported that Eposognatus had failed in persuading the Galatians not to attack and that they were mustering nearby in the mountains.

The Tolostobogii occupied Mount Olympus, while the Tectosagi and the Trocmi went to another mountain. On Mount Olympus, the Galatians had fortified themselves with a ditch and other defensive works. For the first two days, the Romans scouted the mountains. On the third day, the Romans attacked the Galatian position with their skirmishers. The Roman auxiliary archers, slingers and javelinmen inflicted heavy losses on the poorly armored Galatians, while those who attempted to get into close combat were overcame by the superior weapons and armour of the Roman velites. The battle turned to a massacre for the Galatians when the Roman legions finally stormed their camp. The Galatians lost some 10,000 men and had around 40,000 captured during the aftermath.

Battle of Ancyra
After the Roman victory at Mount Olympus, the Tectosagi begged them not to attack them and asked to meet him for a conference halfway between their camp and Ancyra. The main aim of the conference was for the Tectosagi to delay the Roman attack so that they could allow the women and children to retreat across the Halys River. Their other aim was to assassinate Manlius while he was at the conference. While they were going to the conference the Romans saw the Galatian cavalry charging at them. In the skirmish that followed the Galatians overpowered Manlius' small cavalry escort due to their numbers but were driven back when the cavalry that had been accompanying the Roman foragers arrived and forced the Galatians to retreat.

The Romans spent the next two days scouting the surrounding area and on the third day they met the Galatian army consisting of 50,000 men. The Romans started the battle by attacking with their skirmishers. Again the Galatians were decimated by the hail of missiles, so much so that Galatian centre were shattered by the first charge of the legions and fled in the direction of their camp. The flanks stood their grounds for longer but were eventually forced to retreat. The Romans chased them, plundered the Galatian camp as the surviving Galatians fled across the river to join the women, children and the Trocmi.

Aftermath
These two crushing military defeats forced the Galatians to sue for peace. This campaign greatly enriched Vulso and his legions as the Galatians had gathered great wealth through their many conquests in Asia Minor. The Galatians sent envoys to Vulso asking for peace but Vulso, who at the time was hurrying back to Ephesus because winter was approaching, bade them to come to Ephesus.

Vulso remained in Asia Minor for another year. During that time he concluded the Treaty of Apamea with Antiochus and divided the lands of the Asia Minor coast between Pergamum and Rhodes. When the Galatian envoys came, Vulso told them that King Eumenes II of Pergamum would give them the terms of the peace when he arrived back from Rome.

Vulso began his return journey to Rome in 188 BC and arrived in 187 BC. When he returned to Rome, he received much criticism because of his unauthorised war against the Galatians. However, he eventually overcame the arguments and was awarded a triumph by the Senate.

Citations

References

Primary sources
Livy, translated by Henry Bettison, (1976). Rome and the Mediterranean. London: Penguin Classics. .
Polybius, translated by Frank W. Walbank, (1979). The Rise of the Roman Empire. New York: Penguin Classics. .

On-line sources

Wars involving the Roman Republic
Wars involving Pergamon
Ancient Galatia
Wars involving the Celts
189 BC
180s BC conflicts
2nd century BC in the Roman Republic

Galatian War


"The Greater Good" is the 21st episode of the first season of Lost. The episode was directed by David Grossman and written by Leonard Dick. It first aired on May 4, 2005, on ABC. The character of Sayid Jarrah (Naveen Andrews) is featured in the episode's flashbacks.

Plot

Flashbacks
Arrested at Heathrow Airport on trumped-up terrorism charges, Sayid is recruited as an informant by the Australian Secret Intelligence Service and the CIA, who ask him to infiltrate a terrorist cell in Sydney of which his old friend Essam is a member. After they explain that they know where Nadia is, he agrees. It is revealed that after helping her escape several years ago, Sayid left Iraq and has been travelling the world trying to find her ever since. Sayid flies to Sydney and infiltrates the terrorist cell, telling the agents that Essam is in over his head, and that he can bring him in. The agents tell him to convince Essam to go ahead with the suicide bombing so that he will lead them to the explosives, and threaten Nadia's life when Sayid attempts to refuse. On the day of the attack, Sayid reveals he is an informant, and a distraught Essam kills himself. After Essam's death, the agents tell Sayid where Nadia is living in California, and hand him a plane ticket and money. Sayid inquires about Essam's body, and is told that because no one will claim it, the body will be burned. Sayid insists on claiming the body himself, as Essam was a Muslim man (and Muslims believe in burial, not cremation). Upon being told that his flight is in two hours so he cannot claim the body, Sayid asks them to reschedule his flight for the next day, to which they agree.

On the Island
At the caves, Sayid observes a mourning Shannon Rutherford (Maggie Grace), before asking if he can do anything for her.  At the same time, Kate Austen (Evangeline Lilly) tracks down an exhausted and obstinate Jack Shephard (Matthew Fox). Jack blames John Locke (Terry O'Quinn) for Boone Carlyle's (Ian Somerhalder) death, but Kate pleads with Jack to return. At the beach, the survivors bury Boone. During the funeral, Locke arrives and attempts to explain what happened, but Jack ignores him and flies into a rage.

Afterward, Jack explains to Sayid, Sun-Hwa Kwon (Yunjin Kim), and Kate that Locke is lying, but they insist that Jack must rest. Locke asks Shannon's forgiveness, to no avail; Shannon instead goes to Sayid and asks if he could do something about Locke for her (implying that she wants him to kill Locke).

Meanwhile, Charlie Pace (Dominic Monaghan) tells Claire Littleton (Emilie de Ravin) that she needs to rest, and though reluctant at first she lets him take care of her baby. Charlie has a tough time getting the baby to stop crying, even having Hugo "Hurley" Reyes (Jorge Garcia) sing the song "I Feel Good" to no avail, but finally discovers that the sound of Sawyer's voice quiets the baby.

Kate attempts to take care of Jack, who stubbornly insists he needs to deal with Locke. Realizing he'd probably try this, Kate drugs his juice and he falls asleep, leaving Sayid free to deal with Locke. Sayid arrives at the caves and begins questioning Locke, asking Locke to show him the Beechcraft. As they walk to it, Sayid interrogates Locke, who realizes just what Sayid is doing. Upon arriving at the plane, their cat-and-mouse game escalates. Sayid tells Locke he knows Locke has a gun, and Locke hands it over. He then reveals that it was he who hit Sayid over the head when he was trying to triangulate the distress signal. This enrages Sayid, who pulls the gun on Locke and questions him about the hatch. Locke lies, saying Boone was talking about the plane's hatches.

Sayid returns to the beach and explains to Shannon that he believes Locke did not mean to harm Boone. This prompts an angry Shannon to take matters into her own hands. Shannon steals the guncase key from a sleeping Jack, and confronts Locke in the jungle. Kate, Jack, and Sayid arrive during the confrontation, but Shannon refuses to back down. Left with no choice, Sayid tackles Shannon just as she fires the gun, the bullet grazing Locke's head.

That night, Sayid visits Locke, who thanks him for saving his life. Sayid replies that he only did it because he believes Locke to be their best chance for survival. He then tells Locke to take him to the hatch.

Reception
17.2 million American viewers tuned into this episode. Chris Carabott from IGN commented "[Boone and Shannon] were both left with very little to do this season. Especially Shannon, whose high point of usefulness was deciphering Rousseau's documents for Sayid. Well, Maggie Grace is given an opportunity to shine and she does an acceptable job as the distraught sibling who is now looking for someone to blame for Boone's death. We finally get to see some real depth to Shannon's character and her quest for vengeance is believable".

References

External links

"The Greater Good" at ABC

Lost (season 1) episodes
2005 American television episodes

pt:The Greater Good (Lost)

The Greater Good (Lost)


Sir John Dankworth, CBE (20 September 1927 - 6 February 2010), was an English jazz composer, saxophonist and clarinetist.  He was widely thought of as Britain's most famous jazz musician.  He had a very big influence in the development of jazz in Britain.  He composed film music and several television theme tunes such as "The Avengers" and "Tomorrow's World".  In his early career he was known as Johnny Dankworth He was the husband of jazz singer Cleo Laine.

Life

Early years
John Dankworth was born in Woodford and grew up in Highams Park, Essex. His father was a sales manager who worked for an electrical engineering firm.  John soon found that he loved jazz.  He played the clarinet in a jazz band when he was still at school.

In 1944 he went to study music at the Royal Academy of Music.  He was playing the saxophone, too, but kept this a secret because jazz was not thought to be  suitable for study at the RAM.

When Dankworth did his National Service with the army, he often played in the army dance bands.  He then got a job playing jazz on the Queen Mary which sailed regularly over the Atlantic Ocean to New York.  In America he heard some of the greatest jazz players, especially Charlie Parker who played bebop.

Career
Back in Britain Dankworth took many jobs to get experience playing in jazz bands.  He was a member of a group called Club Eleven which played together for several years.  He also formed a band called Johnny Dankworth Seven with Frank Holder, who played bebop in the style of Miles Davis.  They started to get well-known, and in 1951 were joined by a young singer called Cleo Laine.

In 1953 the band broke up and Dankworth formed his first big band.  It had eight brass instruments, five saxophones, a rhythm section and vocalists.  The group was redesigned in 1956 when he put in a group of soloists instead of the saxophones.  They often played on the radio and brought in guest artists who were not necessarily jazz musicians, e.g. the clarinettist Jack Brymer and the violinist Kenneth Essex as well as the music comedian and cartoonist Gerard Hoffnung.

In 1960 he gave up playing in the band to spend more time on composition. He wrote some very successful film music, e.g. The Servant, Darling, Modesty Blaise and Morgan, A Suitable Case for Treatment. He wrote the television theme for The Avengers and Tomorrow's World, as well as lots of music for television adverts.  He composed a musical version of Lysistrata together with Benny Green for the Bath Festival.

In 1958 he married Laine. He wrote many songs for her and played the beautiful accompaniments, often on the clarinet.

In 1969 they built a concert hall called The Stables in their garden in Wavendon in Milton Keynes.  It became an important centre for concerts, educational programmes and cultural events.

Dankworth and Laine have two children: Alec who is a double bass player and Jacqui who is a singer. John formed a band which included Alec playing the double bass.

Dankworth set up scholarships for young musicians and often worked with young people.  He encouraged educational work at The Stables.  He continued to work hard until shortly before his death.

Dankworth died in hospital in London on 6 February 2010.  His death was announced a few hours later by Laine, who spoke to the audience at the end of a concert in The Stables.  She had told the performers before the concert began.  She wanted the concert to be a celebration of his life. Alec and Jacqui were both performing in the show.

Honours
Dankworth was made a CBE in 1974 and was given a knighthood in 2006.

References
•The Daily Telegraph, 8 February 2010 p. 31: Sir John Dankworth – Obituary

1927 births
2010 deaths
British jazz musicians
British saxophonists
British clarinetists
Jazz composers
Knights Bachelor
Musicians from Essex

John Dankworth


The Stone Lakes National Wildlife Refuge, located south of Sacramento, California, lies within the Sacramento-San Joaquin delta, the destination of thousands of migrating waterfowl, shorebirds, and other water birds. The refuge was established in 1994.

Habitats
Through a number of innovative partnerships, the refuge is protecting scarce natural habitats and agricultural resources in an area threatened by urban sprawl and agricultural changes. Stone Lakes National Wildlife Refuge contains both seasonal and permanent wetlands, riparian forest, and grasslands, as well as some of the last remaining freshwater lakes in the central valley.

These habitats support large populations of migratory water birds, a major rookery for several colonial nesting species such as great blue herons, and a warm water fishery. Several endangered, threatened, and special-status species benefit from these habitats: the valley elderberry longhorn beetle, Swainson's hawk, and greater sandhill crane.

Visitors
Visitor numbers increase every year; they topped 8,500 in 2001, despite a lack of developed facilities such as a visitor education center and restrooms. Volunteers from the local area dedicate their time on weekends guiding visitors through grasslands and tree-lined waterways to educate the public about the refuge in their backyard.

References

External links

official Stone Lakes National Wildlife Refuge website
Stone Lakes National Wildlife Refuge profile

National Wildlife Refuges in California
Protected areas of Sacramento County, California
Parks in the San Joaquin Valley
Natural history of the Central Valley (California)
Protected areas established in 1994
Wetlands of California
Landforms of Sacramento County, California

Stone Lakes National Wildlife Refuge


Jean Drapeau Park (formerly called Parc des Îles) is the third-largest park in Montreal, Quebec, Canada. It comprises two islands, Saint Helen's Island and the artificial island Notre Dame Island, situated off the shore of Old Montreal in the Saint Lawrence River.

The islands were the site of the Expo 67 World's Fair. Notre Dame Island was constructed for the exposition, and Saint Helen's Island artificially extended at its north and south ends. The park was renamed in honour of Jean Drapeau, the late mayor of Montreal and initiator of Expo 67.

History
Saint Helen's Island was discovered by French explorer Samuel de Champlain in 1611, who named it in honour of his wife, Hélène de Champlain, née Boullé. It also bears the name of Helena, mother of Roman emperor Constantine the Great.

The island belonged to the family of Le Moyne de Longueuil from 1665 until 1818, when it was sold to the British government. The British built a fort, a magazine and a bunker after the War of 1812. The new Canadian government acquired it in 1870, and it was converted into a park in 1874.

The islands of the archipelago were chosen as the site of Man and His World (Expo 67). To prepare for this role, Mayor Jean Drapeau expanded Saint Helen's Island and consolidated it with several neighboring islands (including Round Island) and created Notre Dame Island using the fill excavated during the construction of the Montreal Metro in the early 1960s. 28 million tons of fill were needed for this massive undertaking. When the work was completed, Notre-Dame Island and St. Helen's Island hosted Expo 67, which featured pavilions from over sixty countries.

After the closing of Expo in late 1967, the site continued its fair vocation under the name Man and His World until 1984, and finally, most facilities were dismantled and the island was converted into a park. In 1999, the Parc des Îles de Montreal was renamed Parc Jean-Drapeau in honour of former Mayor of Montreal, Jean Drapeau, who had re-shaped the islands, built the Montreal Metro and brought Expo 67 to the city.

Attractions
Summer is the high season for the park, as the majority of attractions are open to the public. These include:
An amusement park, La Ronde operated by Six Flags under an emphyteutic lease
The Montreal Casino
An environmental museum at the Montreal Biosphere (United States pavilion during Expo 67)
The early Victorian Era fortifications at Saint Helen Island Fort
A Formula One race track, the Circuit Gilles Villeneuve, which hosts the Canadian Grand Prix
The city's largest outdoor concert venue, regularly hosting the Vans Warped Tour, Osheaga Festival and Heavy MTL, and as of 2014, an EDM festival known as île Soniq
An Olympic rowing basin
An aquatics centre, which hosted the 2005 World Aquatics Championships
A beach, Plage Jean-Doré

During winter for several weekends, the park throws the winter carnival Fête des neiges de Montréal which is a free event that offers a variety of winter activities.

The islands also boast numerous hiking and skiing trails, bike paths, large athletic grounds and diverse other services and conveniences. During the more temperate months, a diverse array of free and pay activities are offered on a weekly basis in addition to the aforementioned attractions. There's also a weekly electronic dance festival located under Alexander Calder's sculpture Man, commissioned for Expo 67.

The islands are also notable for the remnants of Expo 67, most of which are still in use, though few are still standing. The American and French pavilions are the best preserved, functioning today as the Biosphere and Casino respectively. The Canadian pavilion contains administrative offices, rental halls, and is the site of the studio of Radio-Classique Montréal. The former Tunisian and Jamaican pavilions are also in use, the former for bike rentals while the latter is used principally for receptions.

A considerable portion of Île Notre-Dame was redeveloped into an intricate and elaborate flower garden in the early 1980s, which remains today. The only other significant remnant of the former World's Fair is the Place des Nations at the western end of Île Sainte-Hélène, though this is abandoned and officially off-limits. As such, it's become a popular spot for fishing.

A snowboarding park was added in winter 2009.

See also
Hochelaga Archipelago
Rubicon Riders, Montreal Dragon Boat Racing Team

References

Jean-Drapeau
Music venues in Montreal
Expo 67
1874 establishments in Canada
1874 establishments in Quebec
Festival venues in Canada

Parc Jean-Drapeau


A buffer solution is chemical solution which resists change to its pH or acidity.

It is a solution in water of a mixture of a weak acid or base and its salt. The pH of the solution changes very little when a small amount of strong acid or base is added to it. Buffer solutions are used as a means of keeping pH at a nearly constant value in a wide variety of chemical applications. Many life forms have a relatively small pH range; an example of a buffer solution is blood.

Buffer solutions may be of two types: acidic and basic.
Acidic : A solution of mixture of weak acid and a salt of this acid with a strong base.
eg. CH3COOH+CH3COONa
Basic : A solution of a mixture of weak base and its salt with a strong acid .
eg. NH4OH+NH4Cl

If you add acid to the solution, the concentration of H+ ions will increase; to keep equilibrium a small number of ions will be combined (forming salt and reducing the concentration of H+ ion in the solution). If you add base the concentration of H+ ion will reduce (by consumption  or combining) and so a small amount of salt will break into ions and maintain the pH.

Buffer index is the number of moles of acid or base added to 1 litre of buffer solution to change its ph by 1 unit

Acids

Buffer solution


The Maya calendar is a system of calendars and almanacs used in the Maya civilization of pre-Columbian Mesoamerica, and in some modern Maya communities in highland Guatemala.

It shares many aspects with calendars employed by other earlier Mesoamerican civilizations, such as the Zapotec and Olmec, and contemporary or later ones such as the Mixtec and Aztec calendars. Although the Mesoamerican calendar did not originate with the Maya, their subsequent extensions and refinements of it were the most sophisticated. Along with those of the Aztecs, the Maya calendars are the best-documented and most completely understood.

Types
There are three main Maya calendars: the 260 day ritual calendar called Tzolk'in, the 365 day Haab''', and the Long Count''. Approximately 52 years pass before the Haab and Tzolkin calendars converge and are back in the same alignment. This is called the Calendar round. The Tzolk'in is still in use today by the Ixil, Kek'chi and Quiche peoples of the Guatemalan highlands.

Here is an example of a Maya calendar date: 126.96.36.199.6, 3 Cimi 4 Zotz. The "126.96.36.199.6" is the Long Count. Going from right to left, the units are: kin (1 day), uinal (20 kin = 20 days), tun (18 uinal = 360 days), katun (20 tun = approximately 20 years), baktun (20 katun  =394 years). The Long Count was used to track periods of time longer than the 52 years of the Calendar Round. The mythical starting date of the current creation was August 11, 3114 BCE (Gregorian). "3 Cimi" is the Tzolkin date. The Tzolkin date is a combination of thirteen days numbered one-thirteen and twenty day-names. "4 Zotz" is the Haab' date. The Haab' year contains 18 months (each named) with 20 days each. The number before the word is the day of that month. The Maya then added five days to the calendar after the last month, Cumku, ends, in order to make the year 365 days long. Those five days, called "Uayeb," were considered to be unlucky.

December 21, 2012
A common conspiracy theory myth about the Maya calendar was that it predicted that the world would end on December 21, 2012. This belief was mistaken. According to the Maya, there were three previous worlds. The first began with "the creation of the Earth, and it had upon it vegetation and living beings. Unfortunately, because they lacked speech, the birds and animals were unable to pay homage to the gods and were destroyed. In the second and third Ages the gods created humans of mud and then wood, but these also failed to please and were wiped out. The "zero date" 184.108.40.206.0 on the Long Count was when, according to the Maya, the third world ended and the fourth one, the current world, began. Another 22.214.171.124.0 would occur on December 21, 2012. There is no evidence that the Long Count would end on 188.8.131.52.0 or that the Maya believed that this would be the date of the apocalypse. Still, a variety of popular books and movies have contributed to the publicity surrounding the Maya calendar's supposed prediction of the end of the world in 2012. Some believershave taken advantage of this publicity to sell guides to surviving the apocalypse.

References

Other websites

 Maya Cycles of Time  at Convergence
 Maya Calendar and Links on diagnosis2012.co.uk
 Interactive Maya Calendars
  1897 text by Cyrus Thomas
 Maya Calendar, Date conversions, contemporary year version, Tzolkin and Haab day in Calendar Rounds
 Daily Aztec Calendar Also does Maya long count dates.

Astronomy
Astrology

Calendars

Maya calendar


The Fifie is a design of sailing boat developed on the east coast of Scotland. It was a traditional fishing boat used by Scottish fishermen from the 1850s until well into the 20th century. These boats were mainly used to fish for herring using drift nets, and along with other designs of boat were known as herring drifters.

Design
While the boats varied in design, they can be categorised by their vertical stem and stern, their long straight keel and wide beam. These attributes made the Fifies very stable in the water and allowed them to carry a very large set of sails. The long keel, however, made them difficult to manoeuvre in small harbours.

Sailing Fifies had two masts with the standard rig consisting of a main dipping lug sail and a mizzen standing lug sail. The masts were positioned far forward and aft on the boat to give the maximum clear working space amidships. A large fifie could reach just over  in length. Because of their large sail area they were very fast sailing boats.

Fifies built after 1860 were all decked and from the 1870s onwards the bigger boats were built with carvel planking, i.e. the planks were laid edge to edge instead of the overlapping clinker style of previous boats. The introduction of steam powered capstans in the 1890s, to help raising the lugs sails, allowed the size of these vessels to increase from  to over  in length. From about 1905 onwards sailing Fifies were gradually fitted with engines and converted to motorised vessels.

There are few surviving examples of this type of fishing boat still in existence. The Scottish Fisheries Museum based in Anstruther, Fife has restored and still sails a classic example of this type of vessel named the Reaper. The Swan Trust in Lerwick, Shetland have restored and maintain another Fifie, The Swan, as a sail training vessel. She now takes over 1000 trainees each year, and has taken trainees to participate in the Cutty Sark Tall Ships Races to ports in France, Denmark, the Netherlands, Ireland as well as around the UK. The Isabella Fortuna is owned by the Wick Society.

Gallery

References

External links
 The Reaper - The Boats that Built Britain - Tom Cunliffe
 The history of herring fishing on the east coast of Scotland
 Scottish Fisheries Museum
 The Swan Trust

Sailboat types
Types of fishing vessels
Fishing in Scotland
Ships of Scotland
Scottish design
Sailing in Scotland
1850s establishments in Scotland

Fifie


Norma Talmadge (May 2, 1894 – December 24, 1957) was an American actress and movie producer. She appeared mostly in silent movies and melodramas. Her most famous movie was Smilin' Through in 1922. She was also in Secrets in 1924 and The Lady the following year. Talmadge was regarded as one of the most glamorous and elegant movie stars in the roaring twenties. However, by the end of the silent movie era, her popularity with movie audiences declined.

Talmadge was born in Jersey City, New Jersey in 1894. She died from pneumonia in Las Vegas at the age of sixty-three.

1894 births
1957 deaths
American movie actors
Actors from New Jersey
People from Jersey City, New Jersey
Deaths from pneumonia

Norma Talmadge


Cassius Milton Wicker  (August 25, 1844 – November 2, 1913) was a railroad manager and banker.

The Railroads
Wicker  began his railroad career at twenty-one as a check clerk for the Star-Union Line in East St. Louis, moving up to cashier for the People's Dispatch, Chinese emigrant agent for the North Missouri Railway, and assistant general freight agent for the North Missouri Railway. In 1871 he became assistant general freight agent for the Chicago and North Western Railway, where he had the duty of settling the claims for the losses in the Great Chicago Fire of 1871. In 1876 he moved to the Baltimore and Ohio Railroad as a general agent, assistant general freight agent, traffic manager for the Trans-Ohio division, mining manager in Northern Michigan, and general manager of the B&O's Illinois coal mines. In 1882 he became a commissioner for the Chicago Freight Bureau. In 1887 he was named vice-president of the Colorado Eastern Railway and in 1889 president of the Zanesville and Ohio River Railway. Concurrently he was also a vice-president of the Fort Worth and Rio Grande Railway, the Brooklyn, Queens County and Suburban Railroad, president of the Hudson Valley Railway, the Denver Railroad, Land and Coal Company, the Dillon-Griswold Wire Company, and president of North Shore Traction Company (which owned the Lynn and Boston Railway and controlling stocks in many others).

The Banks
Wicker was also a trustee and vice-president at the Washington Savings Bank, chairman of the board of the Bank of Discount, president of the Bankers' Money Association, and director of Aetna.

Personal life
Wicker was born August 25, 1846, the son of Cyrus Washburn Wicker and Maria Delight (née Halladay) in North Ferrisburgh, Vermont. He was educated in the "little red school house" at North Ferrisburg and at the Williston and Middlebury Academies.  Three of his ancestor were on the Mayflower: William Latham, Elder Brewster, and Mary Chilton. On June 5, 1872, he married Augusta Carroll French (1849–1889)  the daughter of former Illinois Governor Augustus C. French becoming the brother-in-law of Edward French and the uncle to poet Nora May French. They had three children Henry Halladay Wicker, Lucy Southworth Wicker, and Cyrus French Wicker. Cassius M. Wicker died in 1913.

References

1846 births
1913 deaths
American bankers
American railway entrepreneurs
People from Ferrisburgh, Vermont
Chicago and North Western Railway
Baltimore and Ohio Railroad people
19th-century American Episcopalians
19th-century American businesspeople

Cassius Milton Wicker


The Derby Sketching Club is a members' club meeting in Derby, England. It was founded in 1887, still providing members with facilities.

History
In 1887, a group of young men held a meeting at the County hotel in Derby and founded the Derby Sketching Club. They wanted to have a place where they and others could work, share their interest in painting and sketching. The fee for one year was two shillings and sixpence. Their first exhibition was held in January 1889, at the Athenaeum Rooms in Derby.

In 1922, the Derby Ladies Art Group was formed. The two groups first held a joint Exhibition in 1951 for the Festival of Britain. They finally merged in 1966.

The art collector Alfred E. Goodey. collected some of their work about Derby made by Sketching Club members. In the 1940s he presented the paintings to Derby Museum and Art Gallery.

Current activities
There are regular sessions for members- for lifedrawing, and portrait painting and still life. There are guest lectures and exhibitions and members use the website to promote their work.

References

Other websites

Derby
1887 establishments in Europe
1880s establishments in England

Derby Sketching Club


The Sprinter is a family of diesel multiple unit trains in use on the UK railway system. They were built in the 1980s and early 1990s by BREL, Metro Cammell and Leyland. All are based around a Cummins engine with Voith hydraulic transmission. Sprinters can be seen operating in almost every part of the UK, from rural branch lines to commuter expresses into major cities.

British Rail diesel multiple units
British Rail
Multiple units

Sprinter (British Rail)


Slovenia sent people  to compete at the 2018 Winter Paralympics in Pyeongchang, South Korea.  One para-alpine skier was named to the team.  The person was 16-year-old Jernej Slivnik.  He had an injury a few months before the Winter Games started.  He is coached by Roman Podlipnik.  While he was named to the team in 2017, he met all the criteria to compete at the Games in January 2018.

Team

The table below contains the list of members of people (called "Team Slovenia") that will be participating in the 2018 Games.

Para-alpine skiing

Skiers
16-year-old Jernej Slivnik had a shoulder injury five months before the 2018 Games.  He started practicing again at a ski resort in Slovenia in December 2017.  His goal was to be prepared for the 2018 World Cup in Kranjska Gora.  The competition was one of seven World Cup races before the season before the Games.  He was coached by Roman Podlipnik.  He also trained with Slovene deaf skier Anja Drev. His coach was happy in late December. Slivnik was recovering faster than expected from his shoulder injury.  At the end of December 2017, he was the only Slovene to have earned the right to compete at the Paralympics.  Because his recovery went so fast, he competed at a World Cup in Zagreb, Croatia in early December.  This was in addition to the World Cup a week later in Slovenia.  After his first run in Zagreb, he was in thirteenth position.  He did not finish his second run.  His coach was still happy with his performance. At the World Cup in  Kranjska Gora, Slovenia, he finished his races.  The World Cup was only a few days after the World Cup in Zagreb.  While he finished thirteenth, his finishing the World Cup race was very important.  It meant he completed all the things required of him to compete at the 2018 Winter Paralympics.  After the race, his coach said, ""I congratulate Jernejo, because I know he has not been able to do it in the last few weeks. He was injured, but he did not finish the race in Zagreb, even though he was skiing well. Depending on the layout and the conditions on the track it worked well. I expect that now the preparations for the Paralympic Games will be relaxed and fully dedicated." Slivnik said after qualifying for the Paralympics, "Before the first run there were some problems with the track, but the Kranjska Gora team did a great job and prepared a track that was excellent. In the second, the track was already slightly slapped. I made a little mistake, but I did not want to give in, I wanted to aim. I did it. I am glad that I have confirmed my departure for the Paralympic Games, as this idea of successfully passing the game was a long time in the head."

Schedule and results
The first event on the para-alpine program is the downhill. It starts on 10 March, running from 9:30 AM to 1:30 PM. The second event on the program is Super-G. All skiers will race between 9:30 AM and 1:00 PM on 11 March.  The super combined takes place on 13 March. The Super-G part of the event is in the morning. The slalom part is in the afternoon. The slalom event gets underway on 14 March and conclude on 15 March. Women and men both race during the same sessions in the morning. The afternoon sessions start with the women doing their second run. Then the men go.The last para-alpine skiing race of the 2018 Games is the giant slalom. It takes place on 17 - 18 March.  Men and women both race at the same time in the morning sessions.  Women race first in the afternoon sessions, with the men racing a half hour after they end.

References

Nations at the 2018 Winter Paralympics
Sport in Slovenia

Slovenia at the 2018 Winter Paralympics


The Canary Current is a wind-driven surface current that is part of the North Atlantic Gyre. This eastern boundary current branches south from the North Atlantic Current and flows southwest about as far as Senegal where it turns west and later joins the Atlantic North Equatorial Current. The current is named after the Canary Islands. The archipelago (group of islands) partially blocks the flow of the Canary Current (Gyory, 2007).
This wide and slow-moving current is thought to have been exploited in the early Phoenician navigation and settlement along the coast of western Morocco. The ancient Phoenicians not only exploited numerous fisheries within this current zone, but also established a factory at Iles Purpuraires off present day Essaouira for extracting a Tyrian purple dye from a marine gastropod murex species (Hogan, 2007).

Ocean currents

Canary Current