Western theatre: Spain’s Golden Age: The theatre was open to the sky, but an awning could be drawn over the audience to provide protection against sunlight and rain. It was a stage well adapted for rhetoric and poetry, where the imagination of the audience could be stimulated. Furthermore, it was a…

marketing: Purchasing procedures: Under open-bid buying, the government disseminates very specific information about the products and services required and requests bids from suppliers. Contracts generally are awarded to the lowest bidder. In negotiated-contract buying, a government agency negotiates directly with one or more companies regarding a specific project or…

stork: Two open-billed storks, openbills, or shell storks, Anastomus lamelligerus of tropical Africa and A. oscitans of southern Asia, are small storks that eat water snails. When the mandibles of these birds are closed, a wide gap remains except at the tips, probably an adaptation for holding…

gardening: Training and pruning: In the open-centre or vase system, the main stem is terminated and growth forced through a number of branches originating close to the upper end of the trunk. An intermediate system is called the modified-leader system. In espalier systems plants are trained to grow flat along a wire or…

Latin American dance: Social dances: These included open-couple dances, in which couples generally did not touch—such as minuet, allemande, sarabande (zarabande in Spanish), chaconne, galliard, pavane, and volta. The interdependent-couple contredanse (contradanza in Spanish) and its variations (

gas-turbine engine: Idealized simple open-cycle gas-turbine engine: Most gas turbines operate on an open cycle in which air is taken from the atmosphere, compressed in a centrifugal or axial-flow compressor, and then fed into a combustion chamber. Here, fuel is added and burned at an essentially constant pressure with…

magnetohydrodynamic power generator: Coal-fired MHD systems: …arrangement is known as an open-cycle, or once-through, system.

ocean thermal energy conversion: …centred their attention on an open-cycle OTEC system that employs water vapour as the working fluid and dispenses with the use of a refrigerant. In this kind of system, warm surface seawater is partially vaporized as it is injected into a near vacuum. The resultant steam is expanded through a…

metallurgy: Forging: Open-die forging is usually done by hammering a part between two flat faces. It is used to make parts that are too big to be formed in a closed die or in cases where only a few parts are to be made and the cost…

infitāḥ, program of economic liberalization in Egypt initiated by Pres. Anwar Sadat in the early 1970s. Sadat’s program of infitāḥ, officially outlined in the October Paper of April 1974, represented a marked departure from the socialist framework of his predecessor, Gamal Abdel Nasser. The

mutual fund, company that invests the funds of its subscribers in diversified securities and in return issues units representing shares in those holdings. It differs from the investment trust (q.v.), which issues shares in its own capital. In contrast to closed-end investment companies, which have

wrench: …these tools are known as open-end wrenches and are made in various sizes to fit specific bolt and nut sizes.

tunnels and underground excavations: Soft-ground moles: The open-face-wheel type is probably the most common. In the wheel the cutter arm rotates in one direction; in a variant model it oscillates back and forth in a windshield-wiper action that is most suitable in wet, sticky ground. While suitable for firm ground, the open-face…

open-field system, basic community organization of cultivation in European agriculture for 2,000 years or more. Its best-known medieval form consisted of three elements: individual peasant holdings in the form of strips scattered among the different fields; crop rotation; and common grazing. Crop

open-heart surgery, any surgical procedure that requires an incision into the heart, thus exposing one or more of the cardiac chambers, or requires the use of a heart-lung machine, a device that allows circulation and oxygenation of the blood to be maintained outside the patient’s body. The

crucible process: After 1870 the Siemens regenerative gas furnace replaced the coke-fire furnace; it produced even higher temperatures. The Siemens furnace had a number of combustion holes, each holding several crucibles, and heated as many as 100 crucibles at a time. All high-quality tool steel and high-speed steel was long…

open-hearth process, steelmaking technique that for most of the 20th century accounted for the major part of all steel made in the world. William Siemens, a German living in England in the 1860s, seeking a means of increasing the temperature in a metallurgical furnace, resurrected an old proposal

open-market operation, any of the purchases and sales of government securities and sometimes commercial paper by the central banking authority for the purpose of regulating the money supply and credit conditions on a continuous basis. Open-market operations can also be used to stabilize the prices

polynya: Open-ocean polynyas, the larger and longer-lasting of the two types, form within the ice cover and are believed to be caused by the upwelling of deep warmer water. This type is best exemplified by the vast Weddell Polynya in the antarctic Weddell Sea.

open-pit mining, surface mining (q.v.) to obtain minerals other than

pedagogy: The organization of instruction: …ideas are introduced in the open-plan system. At both the primary and the secondary levels, however, there is insufficient evidence on the effectiveness of the systems. The attitude and action of teachers remains the strongest factor, and they may still require some privacy for their teaching.

zoo: Design and architecture: A number of open-range zoos have been established since the early 1930s in rural surroundings. The prototype is Whipsnade Park, established by the Zoological Society of London in 1932. Fewer species of animals are exhibited in such zoos than in urban zoos, but they are kept in more…

resource dependency theory: Open-systems frameworks, on the other hand, stress the impact of the environment, which consists of other organizations, institutions, the professions, and the state. According to the open-systems perspective, an organization will be effective to the extent that it recognizes changes in its environment and adjusts…

organization theory: Key questions, units of analysis, and debates: Last, the open-system perspective argues that one cannot look at an individual organization in isolation. In that view, organizations are intertwined with their environments to the extent that the organization-environment boundary is indistinct.

pingo: …types of pingos are recognized: open-system and closed-system.

freight car: …since the early 1800s: the open-top car, the boxcar, and the flatcar.

chromatography: Subsequent developments: …or Golay, columns, now called open-tubular columns and characterized by their open design and an internal diameter of less than one millimetre, had an explosive impact on chromatographic methodology. It is now possible to separate hundreds of components of a mixture in a single chromatographic experiment.

telecommunications media: Open-wire pair: In order to overcome the insufficiencies of single-wire transmission, the early telephone industry shifted to a two-wire system called the open-wire pair. In an open-wire pair the forward and return conductors are copper wires that run in parallel and in a common plane.…

telecommunications media: Open-wire pair: In order to overcome the insufficiencies of single-wire transmission, the early telephone industry shifted to a two-wire system called the open-wire pair. In an open-wire pair the forward and return conductors are copper wires that run in parallel and in a common plane.…

OpenAI is an American artificial intelligence (AI) research organization consisting of two entities: OpenAI Inc., a nonprofit research segment, and OpenAI Global LLC, a for-profit subsidiary established to commercialize its AI technologies and applications. It was founded in 2015 by a consortium of

stork: Two open-billed storks, openbills, or shell storks, Anastomus lamelligerus of tropical Africa and A. oscitans of southern Asia, are small storks that eat water snails. When the mandibles of these birds are closed, a wide gap remains except at the tips, probably an adaptation for holding…

open-pit mining, surface mining (q.v.) to obtain minerals other than

open-pit mining, surface mining (q.v.) to obtain minerals other than

computer graphics: Processors and programs: The OpenGL (open graphics library) specifies a standard set of graphics routines that may be implemented in computer programming languages such as C or Java. PHIGS (programmer’s hierarchical interactive graphics system) is another set of graphics routines. VRML (virtual reality modeling language) is a graphics description…

chess: Hypermodernism: …a new approach to the opening. The two leading members of the new school, Réti and Nimzowitsch, attacked Tarrasch’s emphasis on building a solid centre in the first dozen moves, starting with 1 e4 or 1 d4. Réti often began a game with 1 Nf3 and did not advance more…

John Cassavetes: Independent filmmaker: 1960s and ’70s: The ambitious Opening Night (1977) also had its problems, including one that often plagued Cassavetes’s films, the perception of excessive length. Nevertheless, Rowlands again excelled as a stage actress suffering an existential crisis after a fan dies on the opening night of her new play. Cassavetes the…

Roger Ebert: …Ebert & the Movies (later Siskel & Ebert). As part of his on-air commentary, Ebert originated the famed thumbs-up, thumbs-down rating system, and the phrase “two thumbs up” was later copyrighted. Each week Ebert and Siskel carried on unscripted discussions of the films they reviewed, and their immense popularity was…

Painesville, city, seat (1840) of Lake county, northeastern Ohio, U.S., near the mouth of the Grand River and Lake Erie, 25 miles (40 km) northeast of Cleveland. The site, first settled permanently by Gen. Edward Paine with a party of 66, was laid out around 1805; it was known variously as The

museum: Early period of reassessment: …museums at Arnhem, Netherlands (Netherlands Open Air Museum; opened 1912), and at St. Fagans, Wales (the Museum of Welsh Life; opened as the Welsh Folk Museum in 1948). The preservation and restoration of buildings or entire settlements in situ also began; particularly well known is Colonial Williamsburg, founded in…

5G: How 5G works: 5G also supports “OpenRoaming” capabilities that allow a user to switch seamlessly and automatically from a cellular to a Wi-Fi connection while traveling, eliminating any interruption of service and the need for entering passwords to access the latter.

non-fungible token: NFT forms and the future: The largest is OpenSea, a peer-to-peer platform that allows members to purchase NFTs directly. Rarible is another open marketplace, while Foundation is moderated by a community of artists who must invite or “upvote” other artists to participate, limiting the size of the marketplace. Lazy allows the display of…

Richard Wagner: Exile: …and Oper und Drama (Opera and Drama). The latter outlined a new, revolutionary type of musical stage work—the vast work, in fact, on which he was engaged. By 1852 he had added to the poem of Siegfrieds Tod three others to precede it, the whole being called Der Ring…

Opéra, Parisian opera house designed by Charles Garnier. The building, considered one of the masterpieces of the Second Empire style, was begun in 1861 and opened with an orchestral concert on Jan. 5, 1875. The first opera performed there was Fromental Halévy’s work La Juive on Jan. 8, 1875. A

opera, a staged drama set to music in its entirety, made up of vocal pieces with instrumental accompaniment and usually with orchestral overtures and interludes. In some operas the music is continuous throughout an act; in others it is broken up into discrete pieces, or “numbers,” separated either

Richard Wagner: Exile: …and Oper und Drama (Opera and Drama). The latter outlined a new, revolutionary type of musical stage work—the vast work, in fact, on which he was engaged. By 1852 he had added to the poem of Siegfrieds Tod three others to precede it, the whole being called Der Ring…

Umberto Eco: 1972, 1976; The Open Work), which suggests that in much modern music, Symbolist verse, and literature of controlled disorder (Franz Kafka, James Joyce) the messages are fundamentally ambiguous and invite the audience to participate more actively in the interpretive and creative process. From that work he went…

opera buffa: …buffa is distinct from French opéra-bouffe, a general term for any light opera.

opera buffa, genre of comic opera originating in Naples in the mid-18th century. It developed from the intermezzi, or interludes, performed between the acts of serious operas. Opera buffa plots centre on two groups of characters: a comic group of male and female personages and a pair (or more) of

Sarah Caldwell: …eventually became known as the Opera Company of Boston, for that city; the company closed in the early 1990s owing to financial difficulties.

Italy: Forces of opposition: …laymen’s organizations were founded; the Opera dei Congressi, with committees at parish level, became the focus of Catholic resistance to the new state. It organized cooperatives, welfare insurance, credit banks and mutual aid societies, as well as a host of local journals and campaigns against liberal secular proposals (such as…

Evangelista Torricelli: In his Opera Geometrica (1644; “Geometric Works”), Torricelli included his findings on fluid motion and projectile motion.

binoculars: Opera glasses and field glasses are binoculars with simple, often inexpensive lens systems and narrow fields of view and are usually made with magnifications of 2.5× to 5×. The lenses used in most binoculars are coated on some or all of their air-to-glass surfaces to…

Berlin: Cultural life: The new Opera House (Deutsche Oper Berlin) was opened in West Berlin in 1961, and it quickly established a position as one of the leading opera houses of the Western world. The Opera House in East Berlin, destroyed in World War II, was rebuilt in 1951; it…

Opéra, Parisian opera house designed by Charles Garnier. The building, considered one of the masterpieces of the Second Empire style, was begun in 1861 and opened with an orchestral concert on Jan. 5, 1875. The first opera performed there was Fromental Halévy’s work La Juive on Jan. 8, 1875. A

theatre: The opera house: There were two kinds of public theatre in the 18th century. One was a logical development of the earlier private court theatres, reflecting a sophisticated, urban, aristocratic demand for theatre as entertainment. The Teatro alla Scala (1776–78) in Milan is a good example…

Berlin: Cultural life: The Opera House in East Berlin, destroyed in World War II, was rebuilt in 1951; it is home to the long-established Deutsche Staatsoper (German National Opera). East Berlin’s Comic Opera also gained fame. Classical music in general finds a distinguished home in Berlin. Foremost among many…

Cairo: Cultural life: The original Baroque Opera House, situated on Opera Square in downtown Cairo, was destroyed by fire in 1971; it was replaced by a modern structure on the southern tip of Jazīrah, completed in 1988.

Eve Queler: …Queler founded in 1971 the Opera Orchestra of New York, which also provided experience to instrumentalists and young singers. Their performances of Claudio Monteverdi’s L’incoronazione di Poppea and Ottorino Respighi’s Belfagor in 1971, Gioacchino Rossini’s William Tell and Giacomo Meyerbeer’s L’Africana in 1972, and other works established the orchestra

Emanuel Swedenborg: Swedenborg’s philosophy of nature: …he published in Leipzig his Opera Philosophica et Mineralia (“Philosophical and Logical Works”) in three folio volumes, the first of which, the Principia Rerum Naturalium (“Principles of Natural Things”), contains Swedenborg’s mature philosophy of nature. In this work he reached by inductive argument several conclusions that resemble the theories of…

Jean Hardouin: …publication in Amsterdam of his Opera Selecta (1708; “Selected Works”), Hardouin was compelled publicly to disavow the theory of a forged antiquity, but a similar theory appeared in his masterwork. This was his edition of the texts of the church councils, from New Testament times onward, Conciliorum Collectio Regia Maxima:…

opera seria, (Italian: “serious opera”), style of Italian opera dominant in 18th-century Europe. It emerged in the late 17th century, notably in the work of Alessandro Scarlatti and other composers working in Naples, and is thus frequently called Neapolitan opera. The primary musical emphasis of

ballet: Ballet as an adjunct to opera: …reflected in the success of opéra-ballets, of which the most celebrated were André Campra’s L’Europe galante (1697; “Gallant Europe”) and Jean-Philippe Rameau’s Les Indes galantes (1735; “The Gallant Indies”). These works combined singing, dancing, and orchestral music into numbers that were unified by a loose theme.

opéra-comique, French form of opera in which spoken dialogue alternates with self-contained musical numbers. The earliest examples of opéra-comique were satiric comedies with interpolated songs, but the form later developed into serious musical drama distinguished from other opera only by its

Marie Van Zandt: …in March 1880 in an Opéra-Comique production of Ambroise Thomas’s Mignon. Her performance there won her a five-year contract, and she attained popular stardom with dizzying speed. The height of her Paris career came in April 1883, when she created the title role in Lakmé, which Leo Delibes reportedly wrote…

operant conditioning, in psychology and the study of human and animal behaviour, a mechanism of learning through which humans and animals come to perform or to avoid performing certain behaviours in response to the presence or absence of certain environmental stimuli. The behaviours are

modinha: …of modinhas are in the Óperas Portuguesas (1733–41) by António José da Silva, who interspersed the songs into the prose dialogue of his dramas. Originally simple melodies, modinhas often were embellished with intricate and elaborate musical effects when performed at court or for the nobility. Modinhas were introduced in Brazil…

opera, a staged drama set to music in its entirety, made up of vocal pieces with instrumental accompaniment and usually with orchestral overtures and interludes. In some operas the music is continuous throughout an act; in others it is broken up into discrete pieces, or “numbers,” separated either

Dame Adeline Genée: …was originally called, became the Royal Academy of Dancing, at the helm of which Genée remained as founder-president until 1954. In 1950 she was made a Dame of the British Empire, the first member of the dance profession to be so honoured.

Andrea Bocelli: …by the press as “popera”) in an effort to expand his audience base. Criticized by some reviewers as being too lightweight to be taken seriously by the opera world, Bocelli nevertheless performed in The Merry Widow in 1999, singing three arias, and made his American operatic debut later that…

modem: Operating parameters: …must follow matching protocols, or operating standards. Worldwide standards for voiceband modems are established by the V-series of recommendations published by the Telecommunication Standardization sector of the International Telecommunication Union (ITU). Among other functions, these standards establish the signaling by which modems initiate and terminate communication, establish compatible modulation and…

operating system (OS), program that manages a computer’s resources, especially the allocation of those resources among other programs. Typical resources include the central processing unit (CPU), computer memory, file storage, input/output (I/O) devices, and network connections. Management tasks

thetan: An operating thetan (OT) is one who not only is free from engrams but also operates as a fully conscious and functioning thetan according to the church’s most sacred teachings.

statistics: Hypothesis testing: A graph known as an operating-characteristic curve can be constructed to show how changes in the sample size affect the probability of making a type II error.

Operation Bagration, large-scale Soviet offensive against Nazi Germany that occurred from June 23 to August 19, 1944, on the Eastern Front during World War II. It was launched in support of the Normandy Invasion. By mid-1944, the Nazis’ military power was in irreversible decline, and Germany’s

Operation Blue Star, Indian military operation in June 1984 ordered by Prime Minister Indira Gandhi to root out a group of militant Sikh separatists who had occupied the Golden Temple, the Sikhs’ holiest shrine. The leader of the group was Jarnail Singh Bhindranwale, a Sikh fundamentalist who

Operation Breadbasket, program begun in 1962 by the Southern Christian Leadership Conference (SCLC) that aimed at improving the economic status of African Americans through a boycott of white-owned and white-operated businesses that refused to employ African Americans or to buy products sold by

Liam Neeson: …a hit man, and in Operation Chromite (2016), about the Inch’ŏn (Incheon) landing during the Korean War, he played U.S. Gen. Douglas MacArthur. Neeson’s other credits from 2016 included A Monster Calls, in which he portrayed the title character, who helps a boy cope with the impending loss of his…

Mohammed bin Salman: In charge of defense and economic policy: Known as Operation Decisive Storm, the campaign intended to give the government of Yemeni Pres. Abd Rabbuh Mansur Hadi a decisive advantage against the Shiʿi Houthi insurgency in the north of the country. It was thought that a Houthi victory might give Iran, Saudi Arabia’s main regional…

Battle of Iwo Jima: Battle: …and Marines to carry out Operation Detachment. At its disposal was an armada of 11 warships that were intended to soften up Japanese defenses with sustained bombardment. Maj. Gen. Harry Schmidt took charge of Marine operations. He fielded the largely veteran 3rd, 4th, and 5th Marine divisions, totaling some 70,000…

Operation Eagle Claw, failed mission by the U.S. military in April 1980 to rescue Americans who were held during the Iran hostage crisis. The mission highlighted deficiencies within the U.S. military command structure and led to the creation of the United States Special Operations Command (SOCOM).

Libya bombings of 1986, U.S. air attacks on selected targets in Libya, launched on April 15, 1986, in retaliation for that country’s perceived terrorist activities. Ten days before the attacks, a bomb exploded in a discotheque in West Berlin frequented by U.S. soldiers, killing two people and

Ben Kingsley: …by the United Nations, and Operation Finale, portraying Adolf Eichmann, a former Nazi officer, as he is tracked and captured in Argentina by a team of secret agents determined to bring him to justice. In 2019 Kingsley played a member of Mossad in both The Red Sea Diving Resort and…

Operation Fortitude, during World War II, an Allied deception operation that was intended to make Nazi Germany’s high command believe that the main Allied invasion of Europe in 1944 would not be at Normandy. Organized by Allied military officials beginning in 1943, Operation Fortitude—which was one

Jason Statham: Acting career: …up for the action comedy Operation Fortune: Ruse de Guerre (2023), about the hunt to find a stolen briefcase.

Operation Just Cause, U.S. military action (December 1989–January 1990) that centred on the invasion of Panama for the purposes of removing Gen. Manuel Noriega, the country’s dictatorial de facto ruler, from power and extraditing him to the U.S. to face charges of drug trafficking and money

Operation Market Garden, Allied pursuit of Nazi Germany’s forces across France, and strategic airborne attempt to advance into Germany during World War II, from September 17 to 27, 1944. Field Marshal Sir Bernard Montgomery persuaded the Supreme Allied Commander, General Dwight D. Eisenhower, to

Colin Firth: …the World War II film Operation Mincemeat (2021), Firth starred with Toni Collette in The Staircase (2022), a true-crime miniseries about the death of a writer’s wife.

Project Paperclip, U.S. government program that sponsored the post-World War II immigration of German and Austrian scientists and technicians to the United States in order to exploit their knowledge for military and industrial purposes. Project Paperclip itself lasted less than two years, but

Ex Parte Quirin: …1941 Nazi plan, known as Operation Pastorius, in which German submarines put two teams of infiltrators ashore in New York and Florida to sabotage defense-related industries in the United States. All of the saboteurs had been born in Germany, lived in the United States, and then returned to their homeland.…

Jamie Lee Curtis: Acting career: …appear in TV shows, notably Operation Petticoat, which was based on a 1959 film starring her father and Cary Grant. The show was canceled in 1978, and that year Jamie Lee Curtis made her big-screen debut, starring in John Carpenter’s Halloween. She played Laurie Strode, a shy studious babysitter terrorized…

Blake Edwards: Early life and work: …hit with the military comedy Operation Petticoat (1959), which starred Cary Grant.

Treblinka: …Belzec and Sobibor—as part of Operation Reinhard, an effort to exterminate the Jews of occupied Poland.

Anselm Kiefer: …Germany’s Spiritual Heroes (1973) and Operation Sea Lion (1975) Kiefer was able to develop an array of visual symbols by which he could continue to comment with irony and sarcasm on certain tragic aspects of German history and culture, in particular the Nazi period. These paintings used garish, sombre colours…

Philip Roth: …he had won previously for Operation Shylock (1993) and The Human Stain. Everyman also marked the start of a period during which Roth produced relatively brief novels, all focused on issues of mortality. Exit Ghost (2007) revisits Zuckerman, who has been reawoken to life’s possibilities after more than a decade…

Operation Torch, major Allied amphibious operation in French North Africa during World War II. It began on November 8, 1942, with the landing of 107,000 British and U.S. troops at Casablanca, Morocco, and the Algerian cities of Algiers and Oran. French authorities concluded an armistice with the

U.S. invasion of Grenada, (October 25, 1983), U.S.-led invasion of the Caribbean country of Grenada to overthrow a military government that had taken power in a bloody coup days earlier. Grenada achieved independence from the United Kingdom on February 7, 1974, and the transition was marked by

Operation Wetback, U.S. immigration law enforcement campaign during the summer of 1954 that resulted in the mass deportation of Mexican nationals—1,100,000 persons according to the U.S. Immigration and Naturalization Service (INS), though most estimates put the figure closer to 300,000. Drafted by

Operation Wrath of God, covert assassination campaign carried out by Israel to avenge the kidnapping and murder of 11 Israeli athletes by Palestinian militants in September 1972 at the Munich Olympics. Although Israel had historically targeted the leaders of organizations such as Fatah, the

Gregory Ratoff: Return to acting: …drama starring Bette Davis, and Operation X (originally called My Daughter Joy), which he also directed; the latter starred Cummins as the daughter of a tycoon (Edward G. Robinson). Ratoff helmed several more films—including Abdullah’s Harem (1955) and Oscar Wilde (1960), his last directing credit—but by then his interest had…

analog computer: Their basic component was an operational amplifier, a device whose output current was proportional to its input potential difference. By causing this output current to flow through appropriate components, further potential differences were obtained, and a wide variety of mathematical operations, including inversion, summation, differentiation, and integration, could be carried…