Miscellany

Jai Ganesh · 2023-09-15 00:59:56

1905) Clown

Gist

A clown is a fool, jester, or comedian in an entertainment (such as a play) specifically : a grotesquely dressed comedy performer in a circus. (ii) : a person who habitually jokes and plays the buffoon.

2) an entertainer who wears funny clothes, has a painted face, and makes people laugh by performing tricks and behaving in a silly way.

Summary

A clown is a familiar comic character of pantomime and circus, known by distinctive makeup and costume, ludicrous antics, and buffoonery, whose purpose is to induce hearty laughter. The clown, unlike the traditional fool or court jester, usually performs a set routine characterized by broad, graphic humour, absurd situations, and vigorous physical action.

The earliest ancestors of the clown flourished in ancient Greece—bald-headed, padded buffoons who performed as secondary figures in farces and mime, parodying the actions of more serious characters and sometimes pelting the spectators with nuts. The same clown appeared in the Roman mime, wearing a pointed hat and a motley patchwork robe and serving as the butt for all the tricks and abuse of his fellow actors.

Clowning was a general feature of the acts of medieval minstrels and jugglers, but the clown did not emerge as a professional comic actor until the late Middle Ages, when traveling entertainers sought to imitate the antics of the court jesters and the amateur fool societies, such as the Enfants san Souci, who specialized in comic drama at festival times. The traveling companies of the Italian commedia dell’arte developed one of the most famous and durable clowns of all time, the Arlecchino, or Harlequin, some time in the latter half of the 16th century, spreading his fame throughout Europe. The Harlequin began as a comic valet, or zany, but soon developed into an acrobatic trickster, wearing a black domino mask and carrying a bat or noisy slapstick, with which he frequently belaboured the posteriors of his victims.

The English clown was descended from the Vice character of the medieval mystery plays, a buffoon and prankster who could sometimes deceive even the Devil. Among the first professional stage clowns were the famous William Kempe and Robert Armin, both of whom were connected with Shakespeare’s company. Traveling English actors of the 17th century were responsible for the introduction of stage clowns to Germany, among them such popular characters as Pickelherring, who remained a German favourite until the 19th century. Pickelherring and his confederates wore clown costumes that have hardly changed to this day: oversized shoes, waistcoats, and hats, with giant ruffs around their necks.

The traditional whiteface makeup of the clown is said to have been introduced with the character of Pierrot (or Pedrolino), the French clown with a bald head and flour-whitened face who first appeared during the latter part of the 17th century. First created as a butt for Harlequin, Pierrot was gradually softened and sentimentalized. The pantomimist Jean-Baptiste-Gaspard Deburau took on the character in the early 19th century and created the famous lovesick, pathetic clown, whose melancholy has since remained part of the clown tradition.

The earliest of the true circus clowns was Joseph Grimaldi, who first appeared in England in 1805. Grimaldi’s clown, affectionately called “Joey,” specialized in the classic physical tricks, tumbling, pratfalls, and slapstick beatings. In the 1860s a low-comedy buffoon appeared under the name of Auguste, who had a big nose, baggy clothes, large shoes, and untidy manners. He worked with a whiteface clown and always spoiled the latter’s trick by appearing at an inappropriate time to foul things up.

Grock (Adrien Wettach) was a famous whiteface pantomimist. His elaborate melancholy resembled that of Emmett Kelly, the American vagabond clown. Bill Irwin maintained the tradition in performances billed as “new vaudeville,” while Dario Fo, an Italian political playwright, carried the torch in a more dramatic context, through both his plays and his personal appearance.

The clown figure in motion pictures culminated in the immortal “little tramp” character of Charlie Chaplin, with his ill-fitting clothes, flat-footed walk, and winsome mannerisms.

Details

A clown is a person who performs comedy and arts in a state of open-mindedness using physical comedy, typically while wearing distinct makeup or costuming and reversing folkway-norms.

History

The most ancient clowns have been found in the Fifth Dynasty of Egypt, around 2400 BC. Unlike court jesters,[dubious – discuss] clowns have traditionally served a socio-religious and psychological role, and traditionally the roles of priest and clown have been held by the same persons. Peter Berger writes, "It seems plausible that folly and fools, like religion and magic, meet some deeply rooted needs in human society." For this reason, clowning is often considered an important part of training as a physical performance discipline, partly because tricky subject matter can be dealt with, but also because it requires a high level of risk and play in the performer.

In anthropology, the term clown has been extended to comparable jester or fool characters in non-Western cultures. A society in which such clowns have an important position are termed clown societies, and a clown character involved in a religious or ritual capacity is known as a ritual clown.

A Heyoka is an individual in Lakota and Dakota culture cultures who lives outside the constraints of normal cultural roles, playing the role of a backwards clown by doing everything in reverse. The Heyoka role is sometimes best filled by a Winkte.

Many native tribes have a history of clowning. The Canadian clowning method developed by Richard Pochinko and furthered by his former apprentice, Sue Morrison, combines European and Native American clowning techniques. In this tradition, masks are made of clay while the creator's eyes are closed. A mask is made for each direction of the medicine wheel. During this process, the clown creates a personal mythology that explores their personal experiences.

"Grimaldi was the first recognizable ancestor of the modern clown, sort of the Homo erectus of clown evolution. Before him, a clown may have worn make-up, but it was usually just a bit of rouge on the cheeks to heighten the sense of them being florid, funny drunks or rustic yokels. Grimaldi, however, suited up in bizarre, colorful costumes, stark white face paint punctuated by spots of bright red on his cheeks and topped with a blue mohawk. He was a master of physical comedy—he leapt in the air, stood on his head, fought himself in hilarious fisticuffs that had audiences rolling in the aisles—as well as of satire lampooning the absurd fashions of the day, comic impressions, and ribald songs."

—The History and Psychology of Clowns Being Scary, Smithsonian.

The circus clown tradition developed out of earlier comedic roles in theatre or Varieté shows during the 19th to mid 20th centuries. This recognizable character features outlandish costumes, distinctive makeup, colorful wigs, exaggerated footwear, and colorful clothing, with the style generally being designed to entertain large audiences.

The first mainstream clown role was portrayed by Joseph Grimaldi (who also created the traditional whiteface make-up design). In the early 1800s, he expanded the role of Clown in the harlequinade that formed part of British pantomimes, notably at the Theatre Royal, Drury Lane and the Sadler's Wells and Covent Garden theatres. He became so dominant on the London comic stage that harlequinade Clowns became known as "Joey", and both the nickname and Grimaldi's whiteface make-up design are still used by other clowns.

The comedy that clowns perform is usually in the role of a fool whose everyday actions and tasks become extraordinary—and for whom the ridiculous, for a short while, becomes ordinary. This style of comedy has a long history in many countries and cultures across the world. Some writers have argued that due to the widespread use of such comedy and its long history it is a need that is part of the human condition.

The modern clowning school of comedy in the 21st century diverged from white-face clown tradition, with more of an emphasis on personal vulnerability.

Origin

The clown character developed out of the zanni rustic fool characters of the early modern commedia dell'arte, which were themselves directly based on the rustic fool characters of ancient Greek and Roman theatre. Rustic buffoon characters in Classical Greek theater were known as sklêro-paiktês (from paizein: to play (like a child)) or deikeliktas, besides other generic terms for rustic or peasant. In Roman theater, a term for clown was fossor, literally digger; labourer.

The English word clown was first recorded c. 1560 (as clowne, cloyne) in the generic meaning rustic, boor, peasant. The origin of the word is uncertain, perhaps from a Scandinavian word cognate with clumsy. It is in this sense that Clown is used as the name of fool characters in Shakespeare's Othello and The Winter's Tale. The sense of clown as referring to a professional or habitual fool or jester developed soon after 1600, based on Elizabethan rustic fool characters such as Shakespeare's.

The harlequinade developed in England in the 17th century, inspired by Arlecchino and the commedia dell'arte. It was here that Clown came into use as the given name of a stock character. Originally a foil for Harlequin's slyness and adroit nature, Clown was a buffoon or bumpkin fool who resembled less a jester than a comical idiot. He was a lower class character dressed in tattered servants' garb.

The now-classical features of the clown character were developed in the early 1800s by Joseph Grimaldi, who played Clown in Charles Dibdin's 1800 pantomime Peter Wilkins: or Harlequin in the Flying World at Sadler's Wells Theatre, where Grimaldi built the character up into the central figure of the harlequinade.

Modern circuses

The circus clown developed in the 19th century. The modern circus derives from Philip Astley's London riding school, which opened in 1768. Astley added a clown to his shows to amuse the spectators between equestrian sequences. American comedian George L. Fox became known for his clown role, directly inspired by Grimaldi, in the 1860s. Tom Belling senior (1843–1900) developed the red clown or Auguste (Dummer August) character c. 1870, acting as a foil for the more sophisticated white clown. Belling worked for Circus Renz in Vienna. Belling's costume became the template for the modern stock character of circus or children's clown, based on a lower class or hobo character, with red nose, white makeup around the eyes and mouth, and oversized clothes and shoes. The clown character as developed by the late 19th century is reflected in Ruggero Leoncavallo's 1892 opera Pagliacci (Clowns). Belling's Auguste character was further popularized by Nicolai Poliakoff's Coco in the 1920s to 1930s.

The English word clown was borrowed, along with the circus clown act, by many other languages, such as French clown, Russian (and other Slavic languages) , Greek, Danish/Norwegian klovn, Romanian clovn etc.

Italian retains Pagliaccio, a Commedia dell'arte zanni character, and derivations of the Italian term are found in other Romance languages, such as French Paillasse, Spanish payaso, Catalan/Galician pallasso, Portuguese palhaço, Greek, Turkish palyaço, German Pajass (via French) Yiddish (payats), Russian, Romanian paiață.

20th-century North America

In the early 20th century, with the disappearance of the rustic simpleton or village idiot character of everyday experience, North American circuses developed characters such as the tramp or hobo. Examples include Marceline Orbes, who performed at the Hippodrome Theater (1905), Charlie Chaplin's The Tramp (1914), and Emmett Kelly's Weary Willie based on hobos of the Depression era. Another influential tramp character was played by Otto Griebling during the 1930s to 1950s. Red Skelton's Dodo the Clown in The Clown (1953), depicts the circus clown as a tragicomic stock character, "a funny man with a drinking problem".

In the United States, Bozo the Clown was an influential Auguste character since the late 1950s. The Bozo Show premiered in 1960 and appeared nationally on cable television in 1978. McDonald's derived its mascot clown, Ronald McDonald, from the Bozo character in the 1960s. Willard Scott, who had played Bozo during 1959–1962, performed as the mascot in 1963 television spots. The McDonald's trademark application for the character dates to 1967.

Based on the Bozo template, the US custom of birthday clown, private contractors who offer to perform as clowns at children's parties, developed in the 1960s to 1970s. The strong association of the (Bozo-derived) clown character with children's entertainment as it has developed since the 1960s also gave rise to Clown Care or hospital clowning in children's hospitals by the mid-1980s. Clowns of America International (established 1984) and World Clown Association (established 1987) are associations of semi-professionals and professional performers.

The shift of the Auguste or red clown character from his role as a foil for the white in circus or pantomime shows to a Bozo-derived standalone character in children's entertainment by the 1980s also gave rise to the evil clown character, with the attraction of clowns for small children being based in their fundamentally threatening or frightening nature. The fear of clowns, particularly circus clowns, has become known by the term "coulrophobia."

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Jai Ganesh · 2023-09-16 00:02:48

1906) Welding

Gist

Welding is a fabrication process whereby two or more parts are fused together by means of heat, pressure or both forming a join as the parts cool. Welding is usually used on metals and thermoplastics but can also be used on wood. The completed welded joint may be referred to as a weldment.

Summary

Welding is a fabrication process that joins materials, usually metals or thermoplastics, by using high heat to melt the parts together and allowing them to cool, causing fusion. Welding is distinct from lower temperature techniques such as brazing and soldering, which do not melt the base metal (parent metal).

In addition to melting the base metal, a filler material is typically added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that, based on weld configuration (butt, full penetration, fillet, etc.), can be stronger than the base material. Pressure may also be used in conjunction with heat or by itself to produce a weld. Welding also requires a form of shield to protect the filler metals or melted metals from being contaminated or oxidized.

Many different energy sources can be used for welding, including a gas flame (chemical), an electric arc (electrical), a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding may be performed in many different environments, including in open air, under water, and in outer space. Welding is a hazardous undertaking and precautions are required to avoid burns, electric shock, vision damage, inhalation of poisonous gases and fumes, and exposure to intense ultraviolet radiation.

Until the end of the 19th century, the only welding process was forge welding, which blacksmiths had used for millennia to join iron and steel by heating and hammering. Arc welding and oxy-fuel welding were among the first processes to develop late in the century, and electric resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as world wars drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like shielded metal arc welding, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as gas metal arc welding, submerged arc welding, flux-cored arc welding and electroslag welding. Developments continued with the invention of laser beam welding, electron beam welding, magnetic pulse welding, and friction stir welding in the latter half of the century. Today, as the science continues to advance, robot welding is commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality.

History

The history of joining metals goes back several millennia. The earliest examples of this come from the Bronze and Iron Ages in Europe and the Middle East. The ancient Greek historian Herodotus states in The Histories of the 5th century BC that Glaucus of Chios "was the man who single-handedly invented iron welding". Welding was used in the construction of the Iron pillar of Delhi, erected in Delhi, India about 310 AD and weighing 5.4 metric tons.

The Middle Ages brought advances in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding occurred. In 1540, Vannoccio Biringuccio published De la pirotechnia, which includes descriptions of the forging operation. Renaissance craftsmen were skilled in the process, and the industry continued to grow during the following centuries.

In 1800, Sir Humphry Davy discovered the short-pulse electrical arc and presented his results in 1801. In 1802, Russian scientist Vasily Petrov created the continuous electric arc, and subsequently published "News of Galvanic-Voltaic Experiments" in 1803, in which he described experiments carried out in 1802. Of great importance in this work was the description of a stable arc discharge and the indication of its possible use for many applications, one being melting metals. In 1808, Davy, who was unaware of Petrov's work, rediscovered the continuous electric arc. In 1881–82 inventors Nikolai Benardos (Russian) and Stanisław Olszewski (Polish) created the first electric arc welding method known as carbon arc welding using carbon electrodes. The advances in arc welding continued with the invention of metal electrodes in the late 1800s by a Russian, Nikolai Slavyanov (1888), and an American, C. L. Coffin (1890). Around 1900, A. P. Strohmenger released a coated metal electrode in Britain, which gave a more stable arc. In 1905, Russian scientist Vladimir Mitkevich proposed using a three-phase electric arc for welding. Alternating current welding was invented by C. J. Holslag in 1919, but did not become popular for another decade.

Resistance welding was also developed during the final decades of the 19th century, with the first patents going to Elihu Thomson in 1885, who produced further advances over the next 15 years. Thermite welding was invented in 1893, and around that time another process, oxyfuel welding, became well established. Acetylene was discovered in 1836 by Edmund Davy, but its use was not practical in welding until about 1900, when a suitable torch was developed. At first, oxyfuel welding was one of the more popular welding methods due to its portability and relatively low cost. As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as advances in metal coverings (known as flux) were made. Flux covering the electrode primarily shields the base material from impurities, but also stabilizes the arc and can add alloying components to the weld metal.

World War I caused a major surge in the use of welding, with the various military powers attempting to determine which of the several new welding processes would be best. The British primarily used arc welding, even constructing a ship, the "Fullagar" with an entirely welded hull. Arc welding was first applied to aircraft during the war as well, as some German airplane fuselages were constructed using the process. Also noteworthy is the first welded road bridge in the world, the Maurzyce Bridge in Poland (1928).

During the 1920s, significant advances were made in welding technology, including the introduction of automatic welding in 1920, in which electrode wire was fed continuously. Shielding gas became a subject receiving much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that developed included the use of hydrogen, argon, and helium as welding atmospheres. During the following decade, further advances allowed for the welding of reactive metals like aluminum and magnesium. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major expansion of arc welding during the 1930s and then during World War II. In 1930, the first all-welded merchant vessel, M/S Carolinian, was launched.

During the middle of the century, many new welding methods were invented. In 1930, Kyle Taylor was responsible for the release of stud welding, which soon became popular in shipbuilding and construction. Submerged arc welding was invented the same year and continues to be popular today. In 1932 a Russian, Konstantin Khrenov eventually implemented the first underwater electric arc welding. Gas tungsten arc welding, after decades of development, was finally perfected in 1941, and gas metal arc welding followed in 1948, allowing for fast welding of non-ferrous materials but requiring expensive shielding gases. Shielded metal arc welding was developed during the 1950s, using a flux-coated consumable electrode, and it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted, in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds, and that same year, plasma arc welding was invented by Robert Gage. Electroslag welding was introduced in 1958, and it was followed by its cousin, electrogas welding, in 1961. In 1953, the Soviet scientist N. F. Kazakov proposed the diffusion bonding method.

Other recent developments in welding include the 1958 breakthrough of electron beam welding, making deep and narrow welding possible through the concentrated heat source. Following the invention of the laser in 1960, laser beam welding debuted several decades later, and has proved to be especially useful in high-speed, automated welding. Magnetic pulse welding (MPW) has been industrially used since 1967. Friction stir welding was invented in 1991 by Wayne Thomas at The Welding Institute (TWI, UK) and found high-quality applications all over the world. All of these four new processes continue to be quite expensive due to the high cost of the necessary equipment, and this has limited their applications.

Details

Welding is a technique used for joining metallic parts usually through the application of heat. This technique was discovered during efforts to manipulate iron into useful shapes. Welded blades were developed in the 1st millennium CE, the most famous being those produced by Arab armourers at Damascus, Syria. The process of carburization of iron to produce hard steel was known at this time, but the resultant steel was very brittle. The welding technique—which involved interlayering relatively soft and tough iron with high-carbon material, followed by hammer forging—produced a strong, tough blade.

In modern times the improvement in iron-making techniques, especially the introduction of cast iron, restricted welding to the blacksmith and the jeweler. Other joining techniques, such as fastening by bolts or rivets, were widely applied to new products, from bridges and railway engines to kitchen utensils.

Modern fusion welding processes are an outgrowth of the need to obtain a continuous joint on large steel plates. Rivetting had been shown to have disadvantages, especially for an enclosed container such as a boiler. Gas welding, arc welding, and resistance welding all appeared at the end of the 19th century. The first real attempt to adopt welding processes on a wide scale was made during World War I. By 1916 the oxyacetylene process was well developed, and the welding techniques employed then are still used. The main improvements since then have been in equipment and safety. Arc welding, using a consumable electrode, was also introduced in this period, but the bare wires initially used produced brittle welds. A solution was found by wrapping the bare wire with asbestos and an entwined aluminum wire. The modern electrode, introduced in 1907, consists of a bare wire with a complex coating of minerals and metals. Arc welding was not universally used until World War II, when the urgent need for rapid means of construction for shipping, power plants, transportation, and structures spurred the necessary development work.

Resistance welding, invented in 1877 by Elihu Thomson, was accepted long before arc welding for spot and seam joining of sheet. Butt welding for chain making and joining bars and rods was developed during the 1920s. In the 1940s the tungsten-inert gas process, using a nonconsumable tungsten electrode to perform fusion welds, was introduced. In 1948 a new gas-shielded process utilized a wire electrode that was consumed in the weld. More recently, electron-beam welding, laser welding, and several solid-phase processes such as diffusion bonding, friction welding, and ultrasonic joining have been developed.

Basic principles of welding

A weld can be defined as a coalescence of metals produced by heating to a suitable temperature with or without the application of pressure, and with or without the use of a filler material.

In fusion welding a heat source generates sufficient heat to create and maintain a molten pool of metal of the required size. The heat may be supplied by electricity or by a gas flame. Electric resistance welding can be considered fusion welding because some molten metal is formed.

Solid-phase processes produce welds without melting the base material and without the addition of a filler metal. Pressure is always employed, and generally some heat is provided. Frictional heat is developed in ultrasonic and friction joining, and furnace heating is usually employed in diffusion bonding.

The electric arc used in welding is a high-current, low-voltage discharge generally in the range 10–2,000 amperes at 10–50 volts. An arc column is complex but, broadly speaking, consists of a cathode that emits electrons, a gas plasma for current conduction, and an anode region that becomes comparatively hotter than the cathode due to electron bombardment. A direct current (DC) arc is usually used, but alternating current (AC) arcs can be employed.

Total energy input in all welding processes exceeds that which is required to produce a joint, because not all the heat generated can be effectively utilized. Efficiencies vary from 60 to 90 percent, depending on the process; some special processes deviate widely from this figure. Heat is lost by conduction through the base metal and by radiation to the surroundings.

Most metals, when heated, react with the atmosphere or other nearby metals. These reactions can be extremely detrimental to the properties of a welded joint. Most metals, for example, rapidly oxidize when molten. A layer of oxide can prevent proper bonding of the metal. Molten-metal droplets coated with oxide become entrapped in the weld and make the joint brittle. Some valuable materials added for specific properties react so quickly on exposure to the air that the metal deposited does not have the same composition as it had initially. These problems have led to the use of fluxes and inert atmospheres.

In fusion welding the flux has a protective role in facilitating a controlled reaction of the metal and then preventing oxidation by forming a blanket over the molten material. Fluxes can be active and help in the process or inactive and simply protect the surfaces during joining.

Inert atmospheres play a protective role similar to that of fluxes. In gas-shielded metal-arc and gas-shielded tungsten-arc welding an inert gas—usually argon—flows from an annulus surrounding the torch in a continuous stream, displacing the air from around the arc. The gas does not chemically react with the metal but simply protects it from contact with the oxygen in the air.

The metallurgy of metal joining is important to the functional capabilities of the joint. The arc weld illustrates all the basic features of a joint. Three zones result from the passage of a welding arc: (1) the weld metal, or fusion zone, (2) the heat-affected zone, and (3) the unaffected zone. The weld metal is that portion of the joint that has been melted during welding. The heat-affected zone is a region adjacent to the weld metal that has not been welded but has undergone a change in microstructure or mechanical properties due to the heat of welding. The unaffected material is that which was not heated sufficiently to alter its properties.

Weld-metal composition and the conditions under which it freezes (solidifies) significantly affect the ability of the joint to meet service requirements. In arc welding, the weld metal comprises filler material plus the base metal that has melted. After the arc passes, rapid cooling of the weld metal occurs. A one-pass weld has a cast structure with columnar grains extending from the edge of the molten pool to the centre of the weld. In a multipass weld, this cast structure may be modified, depending on the particular metal that is being welded.

The base metal adjacent to the weld, or the heat-affected zone, is subjected to a range of temperature cycles, and its change in structure is directly related to the peak temperature at any given point, the time of exposure, and the cooling rates. The types of base metal are too numerous to discuss here, but they can be grouped in three classes: (1) materials unaffected by welding heat, (2) materials hardened by structural change, (3) materials hardened by precipitation processes.

Welding produces stresses in materials. These forces are induced by contraction of the weld metal and by expansion and then contraction of the heat-affected zone. The unheated metal imposes a restraint on the above, and as contraction predominates, the weld metal cannot contract freely, and a stress is built up in the joint. This is generally known as residual stress, and for some critical applications must be removed by heat treatment of the whole fabrication. Residual stress is unavoidable in all welded structures, and if it is not controlled bowing or distortion of the weldment will take place. Control is exercised by welding technique, jigs and fixtures, fabrication procedures, and final heat treatment.

There are a wide variety of welding processes. Several of the most important are discussed below.

Forge welding

This original fusion technique dates from the earliest uses of iron. The process was first employed to make small pieces of iron into larger useful pieces by joining them. The parts to be joined were first shaped, then heated to welding temperature in a forge and finally hammered or pressed together. The Damascus sword, for example, consisted of wrought-iron bars hammered until thin, doubled back on themselves, and then rehammered to produce a forged weld. The larger the number of times this process was repeated, the tougher the sword that was obtained. In the Middle Ages cannons were made by welding together several iron bands, and bolts tipped with steel fired from crossbows were fabricated by forge welding. Forge welding has mainly survived as a blacksmith’s craft and is still used to some extent in chain making.

Arc welding

Shielded metal-arc welding accounts for the largest total volume of welding today. In this process an electric arc is struck between the metallic electrode and the workpiece. Tiny globules of molten metal are transferred from the metal electrode to the weld joint. Since arc welding can be done with either alternating or direct current, some welding units accommodate both for wider application. A holder or clamping device with an insulated handle is used to conduct the welding current to the electrode. A return circuit to the power source is made by means of a clamp to the workpiece.

Gas-shielded arc welding, in which the arc is shielded from the air by an inert gas such as argon or helium, has become increasingly important because it can deposit more material at a higher efficiency and can be readily automated. The tungsten electrode version finds its major applications in highly alloyed sheet materials. Either direct or alternating current is used, and filler metal is added either hot or cold into the arc. Consumable electrode gas-metal arc welding with a carbon dioxide shielding gas is widely used for steel welding. Two processes known as spray arc and short-circuiting arc are utilized. Metal transfer is rapid, and the gas protection ensures a tough weld deposit.

Submerged arc welding is similar to the above except that the gas shield is replaced with a granulated mineral material as a flux, which is mounded around the electrode so that no arc is visible.

Plasma welding is an arc process in which a hot plasma is the source of heat. It has some similarity to gas-shielded tungsten-arc welding, the main advantages being greater energy concentration, improved arc stability, and easier operator control. Better arc stability means less sensitivity to joint alignment and arc length variation. In most plasma welding equipment, a secondary arc must first be struck to create an ionized gas stream and permit the main arc to be started. This secondary arc may utilize either a high-frequency or a direct contact start. Water cooling is used because of the high energies forced through a small orifice. The process is amenable to mechanization, and rapid production rates are possible.

Thermochemical processes

One such process is gas welding. It once ranked as equal in importance to the metal-arc welding processes but is now confined to a specialized area of sheet fabrication and is probably used as much by artists as in industry. Gas welding is a fusion process with heat supplied by burning acetylene in oxygen to provide an intense, closely controlled flame. Metal is added to the joint in the form of a cold filler wire. A neutral or reducing flame is generally desirable to prevent base-metal oxidation. By deft craftsmanship very good welds can be produced, but welding speeds are very low. Fluxes aid in preventing oxide contamination of the joint.

Another thermochemical process is aluminothermic (thermite) joining. It has been successfully used for both ferrous and nonferrous metals but is more frequently used for the former. A mixture of finely divided aluminum and iron oxide is ignited to produce a superheated liquid metal at about 2,800 °C (5,000 °F). The reaction is completed in 30 seconds to 2 minutes regardless of the size of the charge. The process is suited to joining sections with large, compact cross sections, such as rectangles and rounds. A mold is used to contain the liquid metal.

Resistance welding

Spot, seam, and projection welding are resistance welding processes in which the required heat for joining is generated at the interface by the electrical resistance of the joint. Welds are made in a relatively short time (typically 0.2 seconds) using a low-voltage, high-current power source with force applied to the joint through two electrodes, one on each side. Spot welds are made at regular intervals on sheet metal that has an overlap. Joint strength depends on the number and size of the welds. Seam welding is a continuous process wherein the electric current is successively pulsed into the joint to form a series of overlapping spots or a continuous seam. This process is used to weld containers or structures where spot welding is insufficient. A projection weld is formed when one of the parts to be welded in the resistance machine has been dimpled or pressed to form a protuberance that is melted down during the weld cycle. The process allows a number of predetermined spots to be welded at one time. All of these processes are capable of very high rates of production with continuous quality control. The most modern equipment in resistance welding includes complete feedback control systems to self-correct any weld that does not meet the desired specifications.

Flash welding is a resistance welding process where parts to be joined are clamped, the ends brought together slowly and then drawn apart to cause an arc or flash. Flashing or arcing is continued until the entire area of the joint is heated; the parts are then forced together and pressure maintained until the joint is formed and cooled.

Low- and high-frequency resistance welding is used for the manufacture of tubing. The longitudinal joint in a tube is formed from metal squeezed into shape with edges abutted. Welding heat is governed by the current passing through the work and the speed at which the tube goes through the rolls. Welding speeds of 60 metres (200 feet) per minute are possible in this process.

Electron-beam welding

In electron-beam welding, the workpiece is bombarded with a dense stream of high-velocity electrons. The energy of these electrons is converted to heat upon impact. A beam-focusing device is included, and the workpiece is usually placed in an evacuated chamber to allow uninterrupted electron travel. Heating is so intense that the beam almost instantaneously vaporizes a hole through the joint. Extremely narrow deep-penetration welds can be produced using very high voltages—up to 150 kilovolts. Workpieces are positioned accurately by an automatic traverse device; for example, a weld in material 13 mm (0.5 inch) thick would only be 1 mm (0.04 inch) wide. Typical welding speeds are 125 to 250 cm (50 to 100 inches) per minute.

Cold welding

Cold welding, the joining of materials without the use of heat, can be accomplished simply by pressing them together. Surfaces have to be well prepared, and pressure sufficient to produce 35 to 90 percent deformation at the joint is necessary, depending on the material. Lapped joints in sheets and cold-butt welding of wires constitute the major applications of this technique. Pressure can be applied by punch presses, rolling stands, or pneumatic tooling. Pressures of 1,400,000 to 2,800,000 kilopascals (200,000 to 400,000 pounds per square inch) are needed to produce a joint in aluminum; almost all other metals need higher pressures.

Friction welding

In friction welding two workpieces are brought together under load with one part rapidly revolving. Frictional heat is developed at the interface until the material becomes plastic, at which time the rotation is stopped and the load is increased to consolidate the joint. A strong joint results with the plastic deformation, and in this sense the process may be considered a variation of pressure welding. The process is self-regulating, for, as the temperature at the joint rises, the friction coefficient is reduced and overheating cannot occur. The machines are almost like lathes in appearance. Speed, force, and time are the main variables. The process has been automated for the production of axle casings in the automotive industry.

Laser welding

Laser welding is accomplished when the light energy emitted from a laser source is focused upon a workpiece to fuse materials together. The limited availability of lasers of sufficient power for most welding purposes has so far restricted its use in this area. Another difficulty is that the speed and the thickness that can be welded are controlled not so much by power but by the thermal conductivity of the metals and by the avoidance of metal vaporization at the surface. Particular applications of the process with very thin materials up to 0.5 mm (0.02 inch) have, however, been very successful. The process is useful in the joining of miniaturized electrical circuitry.

Diffusion bonding

This type of bonding relies on the effect of applied pressure at an elevated temperature for an appreciable period of time. Generally, the pressure applied must be less than that necessary to cause 5 percent deformation so that the process can be applied to finished machine parts. The process has been used most extensively in the aerospace industries for joining materials and shapes that otherwise could not be made—for example, multiple-finned channels and honeycomb construction. Steel can be diffusion bonded at above 1,000 °C (1,800 °F) in a few minutes.

Ultrasonic welding

Ultrasonic joining is achieved by clamping the two pieces to be welded between an anvil and a vibrating probe or sonotrode. The vibration raises the temperature at the interface and produces the weld. The main variables are the clamping force, power input, and welding time. A weld can be made in 0.005 second on thin wires and up to 1 second with material 1.3 mm (0.05 inch) thick. Spot welds and continuous seam welds are made with good reliability. Applications include extensive use on lead bonding to integrated circuitry, transistor canning, and aluminum can bodies.

Explosive welding

Explosive welding takes place when two plates are impacted together under an explosive force at high velocity. The lower plate is laid on a firm surface, such as a heavier steel plate. The upper plate is placed carefully at an angle of approximately 5° to the lower plate with a sheet of explosive material on top. The charge is detonated from the hinge of the two plates, and a weld takes place in microseconds by very rapid plastic deformation of the material at the interface. A completed weld has the appearance of waves at the joint caused by a jetting action of metal between the plates.

Weldability of metals

Carbon and low-alloy steels are by far the most widely used materials in welded construction. Carbon content largely determines the weldability of plain carbon steels; at above 0.3 percent carbon some precautions have to be taken to ensure a sound joint. Low-alloy steels are generally regarded as those having a total alloying content of less than 6 percent. There are many grades of steel available, and their relative weldability varies.

Aluminum and its alloys are also generally weldable. A very tenacious oxide film on aluminum tends to prevent good metal flow, however, and suitable fluxes are used for gas welding. Fusion welding is more effective with alternating current when using the gas-tungsten arc process to enable the oxide to be removed by the arc action.

Copper and its alloys are weldable, but the high thermal conductivity of copper makes welding difficult. Refractory metals such as zirconium, niobium, molybdenum, tantalum, and tungsten are usually welded by the gas-tungsten arc process. Nickel is the most compatible material for joining, is weldable to itself, and is extensively used in dissimilar metal welding of steels, stainlesses, and copper alloys.

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Jai Ganesh · 2023-09-17 00:03:32

1907) Call center

Gist

A Call Center is an office equipped to handle a large volume of telephone calls for an organization (such as a retailer, bank, or marketing firm) especially for taking orders or for providing customer service.

Details

A call center is a centralized department that handles inbound and outbound calls from current and potential customers. Call centers are located either within an organization or outsourced to another company that specializes in handling calls.

What is the difference between a call center and a contact center?

Call centers focus on one communication channel: the telephone. Contact centers provide support from additional channels, such as email, chat, websites and applications. A contact center may include one or more call centers.

Contact centers provide omnichannel support, assisting customers on whichever channel or device they use. Whether an organization chooses a call center or contact center depends on its products and services, the channels on which it provides customer support and the structures of the organization's support teams.

How do call centers work?

Online merchants, telemarketing companies, help desks, mail-order organizations, polling services, charities and any large organization that uses the telephone to sell products or offer services use call centers. These organizations also use call centers to enhance CX.

The three most common types of call centers are inbound, outbound and blended call centers.

Inbound call center. Typically, these call centers handle a considerable volume of calls simultaneously and then screen, forward and log the calls. An interactive voice response (IVR) system can answer calls and use speech recognition technology to address customer queries with an automated message or route calls to the appropriate call center agents or recipients through an automated call distributor (ACD).

Agents in an inbound call center may handle calls from current or potential customers regarding accounts management, scheduling, technical support, complaints, queries about products or services, or intent to purchase from the organization.

Outbound call center. In these call centers, an agent makes calls on behalf of the organization or client for tasks, including lead generation, telemarketing, customer retention, fundraising, surveying, collecting debts or scheduling appointments. To maximize efficiencies, an automated dialer can make the calls and then transfer them to an available agent using an IVR system after the caller connects. Outbound call centers must ensure compliance with the National Do Not Call Registry, a list to which citizens can add their phone numbers to avoid unwanted solicitation calls.

Blended call center. This type of call center handles both inbound and outbound calls.

Importance of call centers

Customers have high expectations for customer service. They want their issues addressed and handled quickly and efficiently. Organizations must have representatives available when customers call for service or support, and those with call centers can more effectively assist customers in need. Call centers can make an organization available 24/7 or during a time window that matches customer expectations.

Customer phone calls have value beyond customer service. With some products or services, phone calls are the only interactions organizations have with customers -- therefore, the only opportunity to personally connect with customers.

Types of call centers

Beyond inbound, outbound and blended, further classifications of call centers include the following:

* In-house call center. The organization owns and runs its call center and hires its agents.
* Outsourced call center. The organization hires a third party to handle calls on its behalf, generally to remove the burdens of hiring and training call center agents and investing in and updating call center technology, which can reduce operating costs.
* Offshore call center. The organization outsources its operations to a company in another country, often to save money on wages and provide services around the clock. Drawbacks to an offshore call center include reduced customer satisfaction due to language issues and a lack of knowledge about the organization, product or service due to distance.
* Virtual call center. The organization employs geographically dispersed agents who answer calls using cloud call center technology. Call center agents work either in smaller groups in different offices or in their own homes.

Call center teams and structure

Many different roles make up call center teams, including agents, team leaders and IT personnel.

Call center agents. Agents are the key point of contact between an organization and its customers, as agents talk directly with customers and handle their calls. Depending on the type of call center, agents may handle either incoming or outgoing calls. Call center agents typically have customer service skills, are knowledgeable about the organization and are creative problem-solvers.

Team leaders. Many call centers split agents into smaller groups for easier management. Team leaders help call center agents deescalate conversations, solve issues or answer questions from customers or the agents. In addition, team leaders should ensure call center agents are happy and fulfilled in their roles.

Call center directors. While team leaders run smaller teams, call center directors run operations and ensure everything runs smoothly. Directors, or managers, set the metrics and expectations for agent performance to ensure they meet the standards for customer expectations and keep the center running smoothly.

Quality assurance team. Quality assurance (QA) is a practice that ensures products or services meet specific requirements, and QA teams put this into practice. These teams can monitor and evaluate agent phone calls in call centers to ensure the call quality and CX are up to the center's standards. In some cases, call center directors run the QA checks.

IT personnel. IT professionals are critical to call centers -- especially those with remote operations. And while IT personnel aren't exclusive to call centers, they ensure agents' technology and tools are up to date to keep the call center running smoothly.

Call center technology

Call centers, at their cores, require two key pieces of technology: computers and headsets. Call center agents need access to computers and reliable headsets to make and receive calls, so their voices sound clear and easy for customers to understand.

Remote call center agents may also require enhanced internet access to access their organizations' call center software reliably, so organizations may want to invest in home networking equipment for remote agents.

Other critical call center technology and software include the following:

* call management software, including ACD technology;
* call monitoring software;
* speech analytics tools;
* workforce management software;
* customer relationship management software;
* IVR software;
* outbound dialers; and
* chatbot or virtual assistant technology.

Examples of call centers across industries

Call centers can benefit any industry that interacts with customers over the phone. Examples include the following:

* Airlines. Customers call airline toll-free numbers to engage with IVR menus or speak to customer service agents. Customers can check flight statuses, obtain flight details and check frequent flyer mileage balances. In addition, flyers can speak to customer service agents to re-book a flight. When weather conditions, such as a large winter storm, cause flight delays or cancellations, airlines can quickly respond to customer needs.
* Healthcare. Customers call healthcare providers to make, change or confirm appointments and to ask physicians questions. When a medical emergency arises off-hours, healthcare providers can use outsourced call centers to receive calls and route them to an on-call physician.
* Retail. Customers call retail businesses for assistance before, during or after purchases. Before or during purchase, a customer may ask a customer service agent about shipping details or the retailer's return policy. After a purchase, customers may call to report a missing item or request a return.

How is call center success measured?

Organizations should track key performance indicators (KPIs) to measure the success rates and efficiency of call centers and agents. The KPIs may vary depending on the center's function: An outbound call center may measure cost per call, revenue earned, total calls made and tasks completed, among other metrics. Inbound call center metrics may include first call resolution (FCR), average wait time and abandoned call rates.

In addition, organizations can use speech analytics software to monitor and analyze call center agent performance. It can identify areas that may require more knowledge and training, which can improve call handling times and FCR.

Related Terms

* customer satisfaction (CSAT)
* Customer satisfaction (CSAT) is a measure of the degree to which a product or service meets customer expectations.
* omnichannel

Omnichannel -- also spelled omni-channel -- is an approach to sales, marketing and customer support that seeks to provide

* virtual agent

A virtual agent -- sometimes called an intelligent virtual agent, virtual rep or chatbot -- is a software program that uses.

Additional Information

A call centre (Commonwealth spelling) or call center (American spelling; see spelling differences) is a managed capability that can be centralised or remote that is used for receiving or transmitting a large volume of enquiries by telephone. An inbound call centre is operated by a company to administer incoming product or service support or information enquiries from consumers. Outbound call centres are usually operated for sales purposes such as telemarketing, for solicitation of charitable or political donations, debt collection, market research, emergency notifications, and urgent/critical needs blood banks. A contact centre is a further extension to call centres telephony based capabilities, administers centralised handling of individual communications, including letters, faxes, live support software, social media, instant message, and email.

A call center was previously seen to be an open workspace for call center agents, with workstations that include a computer and display for each agent and connected to an inbound/outbound call management system, and one or more supervisor stations. It can be independently operated or networked with additional centers, often linked to a corporate computer network, including mainframes, microcomputer/servers and LANs.

The contact center is a central point from which all customer contacts are managed. Through contact centers, valuable information can be routed to the appropriate people or systems, contacts can be tracked and data may be gathered. It is generally a part of the company's customer relationship management infrastructure. The majority of large companies use contact centers as a means of managing their customer interactions. These centers can be operated by either an in-house department responsible or outsourcing customer interaction to a third-party agency (known as Outsourcing Call Centres).

History

Answering services, as known in the 1960s through the 1980s, earlier and slightly later, involved a business that specifically provided the service. Primarily by the use of an off-premises extension (OPX) for each subscribing business, connected at a switchboard at the answering service business, the answering service would answer the otherwise unattended phones of the subscribing businesses with a live operator. The live operator could take messages or relay information, doing so with greater human interactivity than a mechanical answering machine. Although undoubtedly more costly (the human service, the cost of setting up and paying the phone company for the OPX on a monthly basis), it had the advantage of being more ready to respond to the unique needs of after-hours callers. The answering service operators also had the option of calling the client and alerting them to particularly important calls.

The origins of call centers date back to the 1960s with the UK-based Birmingham Press and Mail, which installed Private Automated Business Exchanges (PABX) to have rows of agents handling customer contacts. By 1973, call centers received mainstream attention after Rockwell International patented its Galaxy Automatic Call Distributor (GACD) for a telephone booking system as well as the popularization of telephone headsets as seen on televised NASA Mission Control Center events.

During the late 1970s, call center technology expanded to include telephone sales, airline reservations, and banking systems. The term "call center" was first published and recognised by the Oxford English Dictionary in 1983. The 1980s experienced the development of toll-free telephone numbers to increase the efficiency of agents and overall call volume. Call centers increased with the deregulation of long-distance calling and growth in information-dependent industries.

As call centres expanded, workers in North America began to join unions such as the Communications Workers of America and the United Steelworkers. In Australia, the National Union of Workers represents unionised workers; their activities form part of the Australian labour movement. In Europe, UNI Global Union of Switzerland is involved in assisting unionisation in the call center industry, and in Germany Vereinte Dienstleistungsgewerkschaft represents call centre workers.

During the 1990s, call centres expanded internationally and developed into two additional subsets of communication: contact centres and outsourced bureau centres. A contact centre is a coordinated system of people, processes, technologies, and strategies that provides access to information, resources, and expertise, through appropriate channels of communication, enabling interactions that create value for the customer and organization. In contrast to in-house management, outsourced bureau contact centres are a model of contact centre that provide services on a "pay per use" model. The overheads of the contact centre are shared by many clients, thereby supporting a very cost effective model, especially for low volumes of calls. The modern contact centre includes automated call blending of inbound and outbound calls as well as predictive dialing capabilities, dramatically increasing agents' productivity. New implementations of more complex systems require highly skilled operational and management staff that can use multichannel online and offline tools to improve customer interactions.

Technology:

Call centre technologies include: speech recognition software which allowed Interactive Voice Response (IVR) systems to handle first levels of customer support, text mining, natural language processing to allow better customer handling, agent training via interactive scripting and automatic mining using best practices from past interactions, support automation and many other technologies to improve agent productivity and customer satisfaction. Automatic lead selection or lead steering is also intended to improve efficiencies, both for inbound and outbound campaigns. This allows inbound calls to be directly routed to the appropriate agent for the task, whilst minimising wait times and long lists of irrelevant options for people calling in.

For outbound calls, lead selection allows management to designate what type of leads go to which agent based on factors including skill, socioeconomic factors, past performance, and percentage likelihood of closing a sale per lead.

The universal queue standardises the processing of communications across multiple technologies such as fax, phone, and email. The virtual queue provides callers with an alternative to waiting on hold when no agents are available to handle inbound call demand.

Premises-based technology

Historically, call centres have been built on Private branch exchange (PBX) equipment owned, hosted, and maintained by the call centre operator. The PBX can provide functions such as automatic call distribution, interactive voice response, and skills-based routing.

Virtual call centre

In a virtual call centre model, the call centre operator (business) pays a monthly or annual fee to a vendor that hosts the call centre telephony and data equipment in their own facility, cloud-based. In this model, the operator does not own, operate or host the equipment on which the call centre runs. Agents connect to the vendor's equipment through traditional PSTN telephone lines, or over voice over IP. Calls to and from prospects or contacts originate from or terminate at the vendor's data centre, rather than at the call centre operator's premises. The vendor's telephony equipment (at times data servers) then connects the calls to the call centre operator's agents.

Virtual call centre technology allows people to work from home or any other location instead of in a traditional, centralised, call centre location, which increasingly allows people 'on the go' or with physical or other disabilities to work from desired locations - i.e. not leaving their house. The only required equipment is Internet access, a workstation, and a softphone. If the virtual call centre software utilizes webRTC, a softphone is not required to dial. The companies are preferring Virtual Call Centre services due to cost advantage. Companies can start their call centre business immediately without installing the basic infrastructure like Dialer, ACD and IVRS.

Virtual call centres became increasingly used after the COVID-19 pandemic restricted businesses from operating with large groups of people working in close proximity.

Cloud computing

Through the use of application programming interfaces (APIs), hosted and on-demand call centres that are built on cloud-based software as a service (SaaS) platforms can integrate their functionality with cloud-based applications for customer relationship management (CRM), lead management and more.

Developers use APIs to enhance cloud-based call centre platform functionality—including Computer telephony integration (CTI) APIs which provide basic telephony controls and sophisticated call handling from a separate application, and configuration APIs which enable graphical user interface (GUI) controls of administrative functions.

Call centres that use cloud computing use software that Gartner refers to as "Contact Center as a Service" (or CCaaS, for short) that Gartner defines as "a software as a service (SaaS)-based application that enables customer service organizations to manage multichannel customer interactions holistically in terms of both customer experience and employee experience".

Outsourcing

Outsourced call centres are often located in developing countries, where wages are significantly lower. These include the call centre industries in the Philippines, Bangladesh, and India.

Companies that regularly utilise outsourced contact centre services include British Sky Broadcasting and Orange in the telecommunications industry, Adidas in the sports and leisure sector, Audi in car manufacturing and charities such as the RSPCA.

Industries:

Healthcare

The healthcare industry has used outbound call centre programmes for years to help manage billing, collections, and patient communication. The inbound call centre is a new and increasingly popular service for many types of healthcare facilities, including large hospitals. Inbound call centres can be outsourced or managed in-house.

These healthcare call centres are designed to help streamline communications, enhance patient retention and satisfaction, reduce expenses and improve operational efficiencies.

Hospitality

Many large hospitality companies such as the Hilton Hotels Corporation and Marriott International make use of call centres to manage reservations. These are known in the industry as "central reservations offices". Staff members at these call centres take calls from clients wishing to make reservations or other inquiries via a public number, usually a 1-800 number. These centres may operate as many as 24 hours per day, seven days a week, depending on the call volume the chain receives.

Evaluation:

Mathematical theory

Queueing theory is a branch of mathematics in which models of service systems have been developed. A call centre can be seen as a queueing network and results from queueing theory such as the probability an arriving customer needs to wait before starting service useful for provisioning capacity. (Erlang's C formula is such a result for an M/M/c queue and approximations exist for an M/G/k queue.) Statistical analysis of call centre data has suggested arrivals are governed by an inhomogeneous Poisson process and jobs have a log-normal service time distribution. Simulation algorithms are increasingly being used to model call arrival, queueing and service levels.

Call centre operations have been supported by mathematical models beyond queueing, with operations research, which considers a wide range of optimisation problems seeking to reduce waiting times while keeping server utilisation and therefore efficiency high.

Criticism

Call centres have received criticism for low pay rates and restrictive working practices for employees, which have been deemed as a dehumanising environment. Other research illustrates how call centre workers develop ways to counter or resist this environment by integrating local cultural sensibilities or embracing a vision of a new life. Most call centres provide electronic reports that outline performance metrics, quarterly highlights and other information about the calls made and received. This has the benefit of helping the company to plan the workload and time of its employees. However, it has also been argued that such close monitoring breaches the human right to privacy.

Complaints are often logged by callers who find the staff do not have enough skill or authority to resolve problems, as well as appearing apathetic. These concerns are due to a business process that exhibits levels of variability because the experience a customer gets and results a company achieves on a given call are dependent upon the quality of the agent. Call centres are beginning to address this by using agent-assisted automation to standardise the process all agents use. However, more popular alternatives are using personality and skill based approaches. The various challenges encountered by call operators are discussed by several authors.

Media portrayals

Indian call centres have been the focus of several documentary films, the 2004 film Thomas L. Friedman Reporting: The Other Side of Outsourcing, the 2005 films John and Jane, Nalini by Day, Nancy by Night, and 1-800-India: Importing a White-Collar Economy, and the 2006 film Bombay Calling, among others. An Indian call centre is also the subject of the 2006 film Outsourced and a key location in the 2008 film, Slumdog Millionaire. The 2014 BBC fly on the wall documentary series The Call Centre gave an often distorted although humorous view of life in a Welsh call centre.

Appointment Setting

Appointment setting is a specialized function within call centres, where dedicated agents focus on facilitating and scheduling meetings between clients and businesses or sales representatives. This service is particularly prevalent in various industries such as financial services, healthcare, real estate, and B2B sales, where time-sensitive and personalized communications are essential for effective client engagement.

Lead Generation

Lead generation is a vital aspect of call center operations, encompassing strategies and activities aimed at identifying potential customers or clients for businesses or sales representatives. It involves gathering information and generating interest among individuals or organizations who may have a potential interest in the products or services offered.

Jai Ganesh · 2023-09-18 00:11:58

1908) Fashion designer

Gist

Fashion design is the art of applying design, aesthetics, clothing construction and natural beauty to clothing and its accessories. It is influenced by culture and different trends, and has varied over time and place.

Details

Fashion designers use their technical knowledge and creative flair to work on designs for new and original clothing.

As a fashion designer, you'll research current fashion trends, forecasting what will be popular with consumers, and take inspiration from the world around you to create fresh and original designs.

You'll decide on fabrics, colours and patterns, produce sample designs and adjust them until you're happy with the final product.

You may work to your own brief or be given a brief to work towards, with specifications relating to colour, fabric and budget. In large companies, you're likely to work as part of a team of designers, headed by a creative director, whereas if working for a small company as sole designer or for yourself, you'll be responsible for all the designs.

You'll typically specialise in one area of design, such as sportswear, childrenswear, footwear or accessories.

Types of fashion designer

The main areas of work for fashion designers are:

* high street fashion - this is where the majority of designers work and where garments are mass manufactured (often in Europe or East Asia). Buying patterns, seasonal trends and celebrity catwalk influences play a key role in this design process. It's a commercial, highly media-led area to work in.
* ready-to-wear - established designers create ready-to-wear collections, produced in relatively small numbers.
haute couture - requires large amounts of time spent on the production of one-off garments for the catwalk.
Designs usually endorse the brand and create a 'look'.

Responsibilities

Tasks depend on the market you're working for, but you'll typically need to:

*create or visualise an idea and produce a design by hand or using programs like Adobe Illustrator
* create moodboards to show to clients
* keep up to date with emerging fashion trends as well as general trends relating to fabrics, colours and shapes
* plan and develop ranges, often based on a theme
* work with others in the design team, such as buyers and forecasters, to develop products to meet a brief
* liaise closely with sales, buying and production teams on an ongoing basis to ensure items suit the customer, market and price points
* understand design from a technical perspective, such as producing patterns and technical specifications for designs
* visit trade shows and manufacturers to source, select and buy fabrics, trims, fastenings and embellishments
* adapt existing designs for mass production
* develop a pattern that is cut and sewn into sample garments and supervise the creation of these, including fitting, detailing and adaptations
* oversee production
* negotiate with customers and suppliers
* showcase your designs at fashion and other trade shows
* work with models to try out your designs and also to wear them on the catwalk at fashion shows
* manage marketing, finances and other business activities, if working on a self-employed basis.

Experienced designers with larger companies may focus more on the design aspect, with pattern cutters and machinists preparing sample garments. In smaller companies these, and other tasks, may be part of the designer's role.

Salary

Starting salaries in the fashion industry are often low. Design assistants may start at around £16,000 to £18,000.
A junior designer can expect to earn approximately £25,000 a year.

Typical salaries at senior designer and creative director level range from around £42,000 to in excess of £85,000.
Salaries vary depending on your level of experience, geographical location and type of employer.

Income figures are intended as a guide only.

Working hours

Working hours typically include regular extra hours to meet project deadlines.

What to expect

* The working environment varies between companies, from a modern, purpose-built office to a small design studio. Freelance designers may work from home or in a rented studio.
* With the increase in online retailing, setting up in business or being self-employed is becoming more common, even straight after graduation. Extensive market research and business acumen are critical for any fashion business to succeed.
* The majority of opportunities are available in London and the South East and some large towns and cities in the North West and Scotland, with pockets of industry in the Midlands.
* Career success relies on a combination of creativity, perseverance, resilience and good communication and networking skills.
* There are opportunities to travel to meet suppliers, research new trends and to attend trade and fashion shows, either in the UK or abroad.

Qualifications

Fashion design is a very competitive industry, and you'll typically need a degree, HND or foundation degree in a subject that combines both technical and design skills. Relevant subjects include:

* art and design
* fashion and fashion design
* fashion business
* fashion buying, marketing and communication
* garment technology
* graphic design
* textiles and textile design.

As you research courses, carefully look at the subjects covered, links the department has with the fashion industry and opportunities available for work placements, showcasing your work and building your portfolio.

Although you don't need a postgraduate qualification, you may want to develop your skills in a particular area such as fashion design management, menswear or footwear.

If your degree is unrelated, you'll need to get experience in the industry or a related area, such as fashion retail. You may want to consider taking a postgraduate qualification in fashion or textile design. Search postgraduate courses in fashion and textile design.

Entry without a degree is sometimes possible if you have a background in fashion or art and design, but you'll need to get experience in the industry to develop your expertise.

Skills

You'll need to show:

* creativity, innovation and flair
* an eye for colour and a feel for fabrics and materials
* the ability to generate ideas and concepts, use your initiative and think outside the box
* design and visualisation skills, either by hand or through computer-aided design (CAD)
* technical skills, including pattern cutting and sewing
* garment technology skills and knowledge
* a proactive approach
* commercial awareness and business orientation
* self-promotion and confidence
* interpersonal, communication and networking skills
* the ability to negotiate and to influence others
* teamworking skills
* good organisation and time management.

Work experience

Getting work experience is vital and experience of any kind in a design studio will help you develop your skills and build up a network of contacts within the industry. Experience in retail can be useful too.

During your degree, take opportunities to develop your portfolio through work placements and internships, either in the UK or abroad. Some courses include a sandwich year in a fashion company. This type of placement can offer the opportunity to work on a more extensive project in industry.

Volunteer at fashion events or set up your own fashion show and make contact with photographers looking for fashion designers. Make the most of degree shows to showcase your work and visit fashion and trade shows, such as London Fashion Week, to pick up ideas and tips.

Employers will expect to see a portfolio that clearly demonstrates your ability to design and produce garments and accessories.

Employers

Most fashion and clothing designers work for high street stores and independent labels. They may be employed at an in-house design studio, based in either a manufacturing or retail organisation.

Others work in specialist design studios, serving the couture and designer ready-to-wear markets, and their work may include producing designs for several manufacturing or retailing companies.

However, the top design houses are a relatively small market compared with the high street fashion sector.

Some fashion designers find work overseas with designers based in Europe and the USA. A directory of fashion contact details, including companies and fashion organisations around the world, can be found at Apparel Search.

Opportunities exist for self-employment. Freelance fashion designers can market their work through trade fairs and via agents, or by making contact directly with buyers from larger businesses or niche clothing outlets.

A number of organisations offer specific training and support for setting up a fashion business. The British Fashion Council provides a range of initiatives, and courses and online resources on how to run your own creative business are offered by The Design Trust.

Competition for design jobs is intense throughout the industry, particularly in womenswear design.

Look for job vacancies at:

* Drapersjobs.com
* Fashion United
* Retail Choice
* The Business of Fashion (BoF) Careers

Employment opportunities are often secured via speculative applications and effective networking. It's important to try to build relationships with more established designers and companies, whether you're seeking permanent or freelance openings.

Recruitment agencies, specialist publications and fashion networks are an important source of contacts and vacancies. Specialist recruitment agencies that represent different market levels include:

* Denza International
* Fashion & Retail Personnel
* Indesign

Discover 5 ways to get into fashion design.

Professional development

The culture of the industry is very much that people learn on the job. However, self-development is important throughout your career, and you'll need to take responsibility for keeping your skills and knowledge up to date.

Initially, any training is likely to be related to learning about the practical processes that your employer uses and covering any relevant technological developments. Larger firms may provide business and computer training, which could include computer-aided design (CAD) or other specialist software, such as Photoshop and Illustrator.

Reading the trade press and fashion blogs, attending trade and fashion shows, and visiting suppliers are also important for keeping up to date with trends and fashions.

A range of specialist short courses and one-day workshops related to fashion are offered by the London College of Fashion, part of the University of the Arts London. It's also possible to take a Masters to develop your skills in a particular area of fashion, such as fashion management, pattern and garment technology, or womenswear.

Career prospects

How your career develops will depend on the specific area of design you trained in, the work experience you've built up and your professional reputation. Another influencing factor will be the type of company you work for and the opportunities for career development within it.

Progression may be slow, particularly at the start of your career. Being proactive and making contacts in the industry is essential, especially in a sector where people frequently move jobs in order to progress their career and where there is a lot of pressure to produce new ideas that are commercially viable.

Typically, you'll begin your career as an assistant.

Progression is then to a role with more creative input, involving proposing concepts and design ideas, although you're unlikely to have much influence on major decisions.

With several years' design experience, progression is possible through senior designer roles to the position of head designer or creative director. At this level, you'll have considerable responsibility for overall design decisions and influences for the range, but as this is a management position others will do the actual design work.

Technical director and quality management positions represent alternative progression routes. Other career options in the fashion industry include:

* colourist
* fashion illustrator
* fashion predictor
* fashion stylist
* pattern cutter/grader.

Fashion designers are increasingly becoming involved in homeware and gift design, which can open up new career paths.

There are also opportunities for self-employment or moving into related occupations, such as retail buying, photography, fashion styling or journalism.

Additional Information

Fashion design is the art of applying design, aesthetics, clothing construction and natural beauty to clothing and its accessories. It is influenced by culture and different trends, and has varied over time and place. "A fashion designer creates clothing, including dresses, suits, pants, and skirts, and accessories like shoes and handbags, for consumers. He or she can specialize in clothing, accessory, or jewelry design, or may work in more than one of these areas."

Fashion designers

Fashion designers work in a variety of different ways when designing their pieces and accessories such as rings, bracelets, necklaces and earrings. Due to the time required to put a garment out in market, designers must anticipate changes to consumer desires. Fashion designers are responsible for creating looks for individual garments, involving shape, color, fabric, trimming, and more.

Fashion designers attempt to design clothes that are functional as well as aesthetically pleasing. They consider who is likely to wear a garment and the situations in which it will be worn, and they work within a wide range of materials, colors, patterns, and styles. Though most clothing worn for everyday wear falls within a narrow range of conventional styles, unusual garments are usually sought for special occasions such as evening wear or party dresses.

Some clothes are made specifically for an individual, as in the case of haute couture or bespoke tailoring. Today, most clothing is designed for the mass market, especially casual and everyday wear, which are commonly known as ready to wear or fast fashion.

Structure

There are different lines of work for designers in the fashion industry, which consist of those who work full-time for a singular fashion house or those who are freelance designers. Fashion designers that work full-time for one fashion house, as 'in-house designers', own the designs and may either work alone or as a part of a design team. Freelance designers who work for themselves, sell their designs to fashion houses, directly to shops, or to clothing manufacturers. There are quite a few fashion designers who choose to set up their own labels, which offers them full control over their designs. While others are self-employed and design for individual clients. Other high-end fashion designers cater to specialty stores or high-end fashion department stores. These designers create original garments, as well as those that follow established fashion trends. Most fashion designers, however, work for apparel manufacturers, creating designs of men's, women's, and children's fashions for the mass market. Large designer brands which have a 'name' as their brand such as Abercrombie & Fitch, Justice, or Juicy are likely to be designed by a team of individual designers under the direction of a design director.

Designing a garment

Fashion designers work in various ways, some start with a vision in their head later on move into drawing it on paper or computer , while others go directly into draping fabric onto a dress form, also known as a mannequin. The design process is unique to the designer and it is rather intriguing to see the various steps that go into the process. A designer may choose to work with certain apps that are able to help connect all their ideas together and expand their thoughts to create a cohesive design. When a designer is completely satisfied with the fit of the toile (or muslin), they will consult a professional pattern maker who then makes the finished, working version of the pattern out of card or via a computer program. Finally, a sample garment is made up and tested on a model to make sure it is an operational outfit. Fashion design is expressive, the designers create art that may be functional or non-functional.

History

Modern Western fashion design is often considered to have started in the 19th century with Charles Frederick Worth who was the first designer to have his label sewn into the garments that he created. Before the former draper set up his maison couture (fashion house) in Paris, clothing design and creation of the garments were handled largely by anonymous seamstresses. At the time high fashion descended from what was popularly worn at royal courts. Worth's success was such that he was able to dictate to his customers what they should wear, instead of following their lead as earlier dressmakers had done. The term couturier was in fact first created in order to describe him. While all articles of clothing from any time period are studied by academics as costume design, only clothing created after 1858 is considered fashion design.

It was during this period that many design houses began to hire artists to sketch or paint designs for garments. Rather than going straight into manufacturing, the images were shown to clients to gain approval, which saved time and money for the designer. If the client liked their design, the patrons commissioned the garment from the designer, and it was produced for the client in the fashion house. This designer-patron construct launched designers sketching their work rather than putting the completed designs on models.

Types of fashion

Garments produced by clothing manufacturers fall into three main categories, although these may be split up into additional, different types.

Haute couture

Until the 1950s, fashion clothing was predominately designed and manufactured on a made-to-measure or haute couture basis (French for high-sewing), with each garment being created for a specific client. A couture garment is made to order for an individual customer, and is usually made from high-quality, expensive fabric, sewn with extreme attention to detail and finish, often using time-consuming, hand-executed techniques. Look and fit take priority over the cost of materials and the time it takes to make. Due to the high cost of each garment, haute couture makes little direct profit for the fashion houses, but is important for prestige and publicity.

Ready-to-wear (prêt-à-porter)

Ready-to-wear, or prêt-à-porter, clothes are a cross between haute couture and mass market. They are not made for individual customers, but great care is taken in the choice and cut of the fabric. Clothes are made in small quantities to guarantee exclusivity, so they are rather expensive. Ready-to-wear collections are usually presented by fashion houses each season during a period known as Fashion Week. This takes place on a citywide basis and occurs twice a year. The main seasons of Fashion Week include; spring/summer, fall/winter, resort, swim, and bridal.

Half-way garments are an alternative to ready-to-wear, "off-the-peg", or prêt-à-porter fashion. Half-way garments are intentionally unfinished pieces of clothing that encourage co-design between the "primary designer" of the garment, and what would usually be considered, the passive "consumer". This differs from ready-to-wear fashion, as the consumer is able to participate in the process of making and co-designing their clothing. During the Make{able} workshop, Hirscher and Niinimaki found that personal involvement in the garment-making process created a meaningful "narrative" for the user, which established a person-product attachment and increased the sentimental value of the final product.

Otto von Busch also explores half-way garments and fashion co-design in his thesis, "Fashion-able, Hacktivism and engaged Fashion Design".

Mass market

Currently, the fashion industry relies more on mass-market sales. The mass market caters for a wide range of customers, producing ready-to-wear garments using trends set by the famous names in fashion. They often wait around a season to make sure a style is going to catch on before producing their versions of the original look. To save money and time, they use cheaper fabrics and simpler production techniques which can easily be done by machines. The end product can, therefore, be sold much more cheaply.

There is a type of design called "kutch" originated from the German word kitschig, meaning "trashy" or "not aesthetically pleasing". Kitsch can also refer to "wearing or displaying something that is therefore no longer in fashion".

Income

The median annual wages for salaried fashion designers was $74,410 in February of 2023. The middle 50 percent earned an average of 76,700. The lowest 10 percent earned 32,320 and the highest 10 percent earned 130,900. Median annual earnings in May 2008 were $52,860 (£40,730.47) in apparel, piece goods, and notions - the industry employing the largest numbers of fashion designers. In 2016, 23,800 people were counted as fashion designers in the United States.

Fashion industry

Fashion today is a global industry, and most major countries have a fashion industry. Seven countries have established an international reputation in fashion: the United States, France, Italy, United Kingdom, Japan, Germany and Belgium. The "big four" fashion capitals of the fashion industry are New York City, Paris, Milan, and London.

Jai Ganesh · 2023-09-19 00:13:34

1909) Hydroelectric power

Gist

Hydropower, or hydroelectric power, is one of the oldest and largest sources of renewable energy, which uses the natural flow of moving water to generate electricity.

Summary

Hydroelectric power, also called hydropower, is electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy. In the early 21st century, hydroelectric power was the most widely utilized form of renewable energy; in 2019 it accounted for more than 18 percent of the world’s total power generation capacity.

In the generation of hydroelectric power, water is collected or stored at a higher elevation and led downward through large pipes or tunnels (penstocks) to a lower elevation; the difference in these two elevations is known as the head. At the end of its passage down the pipes, the falling water causes turbines to rotate. The turbines in turn drive generators, which convert the turbines’ mechanical energy into electricity. Transformers are then used to convert the alternating voltage suitable for the generators to a higher voltage suitable for long-distance transmission. The structure that houses the turbines and generators, and into which the pipes or penstocks feed, is called the powerhouse.

Hydroelectric power plants are usually located in dams that impound rivers, thereby raising the level of the water behind the dam and creating as high a head as is feasible. The potential power that can be derived from a volume of water is directly proportional to the working head, so that a high-head installation requires a smaller volume of water than a low-head installation to produce an equal amount of power. In some dams, the powerhouse is constructed on one flank of the dam, part of the dam being used as a spillway over which excess water is discharged in times of flood. Where the river flows in a narrow steep gorge, the powerhouse may be located within the dam itself.

In most communities the demand for electric power varies considerably at different times of the day. To even the load on the generators, pumped-storage hydroelectric stations are occasionally built. During off-peak periods, some of the extra power available is supplied to the generator operating as a motor, driving the turbine to pump water into an elevated reservoir. Then, during periods of peak demand, the water is allowed to flow down again through the turbine to generate electrical energy. Pumped-storage systems are efficient and provide an economical way to meet peak loads.

In certain coastal areas, such as the Rance River estuary in Brittany, France, hydroelectric power plants have been constructed to take advantage of the rise and fall of tides. When the tide comes in, water is impounded in one or more reservoirs. At low tide, the water in these reservoirs is released to drive hydraulic turbines and their coupled electric generators.

Falling water is one of the three principal sources of energy used to generate electric power, the other two being fossil fuels and nuclear fuels. Hydroelectric power has certain advantages over these other sources. It is continually renewable owing to the recurring nature of the hydrologic cycle. It does not produce thermal pollution. (However, some dams can produce methane from the decomposition of vegetation under water.) Hydroelectric power is a preferred energy source in areas with heavy rainfall and with hilly or mountainous regions that are in reasonably close proximity to the main load centres. Some large hydro sites that are remote from load centres may be sufficiently attractive to justify the long high-voltage transmission lines. Small local hydro sites may also be economical, particularly if they combine storage of water during light loads with electricity production during peaks. Many of the negative environmental impacts of hydroelectric power come from the associated dams, which can interrupt the migrations of spawning fish, such as salmon, and permanently submerge or displace ecological and human communities as the reservoirs fill. In addition, hydroelectric dams are vulnerable to water scarcity. In August 2021 Oroville Dam, one of the largest hydroelectric power plants in California, was forced to shut down due to historic drought conditions in the region.

Details

Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. However, when constructed in lowland rainforest areas, where part of the forest is inundated, substantial amounts of greenhouse gases may be emitted.

Construction of a hydroelectric complex can have significant environmental impact, principally in loss of arable land and population displacement. They also disrupt the natural ecology of the river involved, affecting habitats and ecosystems, and siltation and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic.

In 2021, global installed hydropower electrical capacity reached almost 1400 GW, the highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions.

History

Hydropower has been used since ancient times to grind flour and perform other tasks. In the late 18th century hydraulic power provided the energy source needed for the start of the Industrial Revolution. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique, which described vertical- and horizontal-axis hydraulic machines, and in 1771 Richard Arkwright's combination of water power, the water frame, and continuous production played a significant part in the development of the factory system, with modern employment practices. In the 1840s the hydraulic power network was developed to generate and transmit hydro power to end users.

By the late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand arising from the Industrial Revolution would drive development as well. In 1878, the world's first hydroelectric power scheme was developed at Cragside in Northumberland, England, by William Armstrong. It was used to power a single arc lamp in his art gallery. The old Schoelkopf Power Station No. 1, US, near Niagara Falls, began to produce electricity in 1881. The first Edison hydroelectric power station, the Vulcan Street Plant, began operating September 30, 1882, in Appleton, Wisconsin, with an output of about 12.5 kilowatts. By 1886 there were 45 hydroelectric power stations in the United States and Canada; and by 1889 there were 200 in the United States alone.

At the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas. Grenoble, France held the International Exhibition of Hydropower and Tourism, with over one million visitors 1925. By 1920, when 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law. The Act created the Federal Power Commission to regulate hydroelectric power stations on federal land and water. As the power stations became larger, their associated dams developed additional purposes, including flood control, irrigation and navigation. Federal funding became necessary for large-scale development, and federally owned corporations, such as the Tennessee Valley Authority (1933) and the Bonneville Power Administration (1937) were created. Additionally, the Bureau of Reclamation which had begun a series of western US irrigation projects in the early 20th century, was now constructing large hydroelectric projects such as the 1928 Hoover Dam. The United States Army Corps of Engineers was also involved in hydroelectric development, completing the Bonneville Dam in 1937 and being recognized by the Flood Control Act of 1936 as the premier federal flood control agency.

Hydroelectric power stations continued to become larger throughout the 20th century. Hydropower was referred to as "white coal". Hoover Dam's initial 1,345 MW power station was the world's largest hydroelectric power station in 1936; it was eclipsed by the 6,809 MW Grand Coulee Dam in 1942. The Itaipu Dam opened in 1984 in South America as the largest, producing 14 GW, but was surpassed in 2008 by the Three Gorges Dam in China at 22.5 GW. Hydroelectricity would eventually supply some countries, including Norway, Democratic Republic of the Congo, Paraguay and Brazil, with over 85% of their electricity.

Future potential

In 2021 the International Energy Agency (IEA) said that more efforts are needed to help limit climate change. Some countries have highly developed their hydropower potential and have very little room for growth: Switzerland produces 88% of its potential and Mexico 80%. In 2022, the IEA released a main-case forecast of 141 GW generated by hydropower over 2022-2027, which is slightly lower than deployment achieved from 2017-2022. Because environmental permitting and construction times are long, they estimate hydropower potential will remain limited, with only an additional 40 GW deemed possible in the accelerated case.

Modernization of existing infrastructure

In 2021 the IEA said that major modernisation refurbishments are required.

Additional Information

Hydropower, or hydroelectric power, is one of the oldest and largest sources of renewable energy, which uses the natural flow of moving water to generate electricity. Hydropower currently accounts for 28.7% of total U.S. renewable electricity generation and about 6.2% of total U.S. electricity generation.

While most people might associate the energy source with the Hoover Dam—a huge facility harnessing the power of an entire river behind its wall—hydropower facilities come in all sizes. Some may be very large, but they can be tiny, too, taking advantage of water flows in municipal water facilities or irrigation ditches. They can even be “damless,” with diversions or run-of-river facilities that channel part of a stream through a powerhouse before the water rejoins the main river. Whatever the method, hydropower is much easier to obtain and more widely used than most people realize. In fact, all but two states (Delaware and Mississippi) use hydropower for electricity, some more than others. For example, in 2020 about 66% of the state of Washington’s electricity came from hydropower.

In a study led by the National Renewable Energy Laboratory on hydropower flexibility, preliminary analysis found that the firm capacity associated with U.S. hydropower’s flexibility is estimated to be over 24 GW. To replace this capability with storage would require the buildout of 24 GW of 10-hour storage—more than all the existing storage in the United States today. Additionally, in terms of integrating wind and solar, the flexibility presented in existing U.S. hydropower facilities could help bring up to 137 gigawatts of new wind and solar online by 2035.

More Details

Hydroelectric energy, also called hydroelectric power or hydroelectricity, is a form of energy that harnesses the power of water in motion—such as water flowing over a waterfall—to generate electricity. People have used this force for millennia. Over 2,000 years ago, people in Greece used flowing water to turn the wheel of their mill to ground wheat into flour.

How Does Hydroelectric Energy Work?

Most hydroelectric power plants have a reservoir of water, a gate or valve to control how much water flows out of the reservoir, and an outlet or place where the water ends up after flowing downward. Water gains potential energy just before it spills over the top of a dam or flows down a hill. The potential energy is converted into kinetic energy as water flows downhill. The water can be used to turn the blades of a turbine to generate electricity, which is distributed to the power plant’s customers.

Types of Hydroelectric Energy Plants

There are three different types of hydroelectric energy plants, the most common being an impoundment facility. In an impoundment facility, a dam is used to control the flow of water stored in a pool or reservoir. When more energy is needed, water is released from the dam. Once water is released, gravity takes over and the water flows downward through a turbine. As the blades of the turbine spin, they power a generator.

Another type of hydroelectric energy plant is a diversion facility. This type of plant is unique because it does not use a dam. Instead, it uses a series of canals to channel flowing river water toward the generator-powering turbines.

The third type of plant is called a pumped-storage facility. This plant collects the energy produced from solar, wind, and nuclear power and stores it for future use. The plant stores energy by pumping water uphill from a pool at a lower elevation to a reservoir located at a higher elevation. When there is high demand for electricity, water located in the higher pool is released. As this water flows back down to the lower reservoir, it turns a turbine to generate more electricity.

How Widely Is Hydroelectric Energy Used Around the World?

Hydroelectric energy is the most commonly-used renewable source of electricity. China is the largest producer of hydroelectricity. Other top producers of hydropower around the world include the United States, Brazil, Canada, India, and Russia. Approximately 71 percent of all of the renewable electricity generated on Earth is from hydropower.

What Is the Largest Hydroelectric Power Plant in the World?

The Three Gorges Dam in China, which holds back the Yangtze River, is the largest hydroelectric dam in the world, in terms of electricity production. The dam is 2,335 meters (7,660 feet) long and 185 meters (607 feet) tall, and has enough generators to produce 22,500 megawatts of power.

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Jai Ganesh · 2023-09-20 00:09:38

1910) Thermal Power

Gist

Thermal power generation consists of using steam power created by burning oil, liquid natural gas (LNG), coal, and other substances to rotate generators and create electricity.

Summary

Thermal power refers to the energy that is generated by converting heat into electricity. It is the process of producing electricity from a primary source of heat by using a steam turbine, which drives an electrical generator.

The primary source of heat can be obtained from various sources, including burning fossil fuels such as coal, oil, and natural gas, or through nuclear fission.

The heat energy is used to produce steam, which is then directed towards the turbine.

The steam expands as it passes through the turbine blades, causing them to spin and generating electricity.

The electricity is then transmitted to the power grid for distribution to homes and businesses.

Thermal power is a widely used method of generating electricity due to the abundance and accessibility of fossil fuels.

However, it is also a significant contributor to greenhouse gas emissions and environmental pollution.

Efforts are being made to reduce the environmental impact of thermal power by developing more efficient and cleaner energy technologies such as solar, wind, and geothermal power.

What is Thermal Power?