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1 Cierva, Juan de la
SUBJECT AREA: Aerospace[br]b. 21 September 1895 Murcia, Spaind. 9 December 1936 Croydon, England[br]Spanish engineer who played a major part in developing the autogiro in the 1920s and 1930s.[br]At the age of 17, Cierva and some of his friends built a successful two-seater biplane, the BCD-1 (C for Cierva). By 1919 he had designed a large three-engined biplane bomber, the C 3, which unfortunately crashed when its wing stalled (list its lift) during a slow-speed turn. Cierva turned all his energies to designing a flying machine which could not stall: his answer was the autogiro. Although an autogiro looks like a helicopter, its rotor blades are not driven by an engine, but free-wheel like a windmill. Forward speed is provided by a conventional engine and propeller, and even if this engine fails, the autogiro's rotors continue to free-wheel and it descends safely. Cierva patented his autogiro design in 1920, but it took him three years to put theory into practice. By 1925, after further improvements, he had produced a practical rotary-winged flying machine.He moved to England and in 1926 established the Cierva Autogiro Company Ltd. The Air Ministry showed great interest and a year later the British company Avro was commissioned to manufacture the C 6A Autogiro under licence. Probably the most significant of Cierva's autogiros was the C 30A, or Avro Rota, which served in the Royal Air Force from 1935 until 1945. Several other manufacturers in France, Germany, Japan and the USA built Cierva autogiros under licence, but only in small numbers and they never really rivalled fixed-wing aircraft. The death of Cierva in an airliner crash in 1936, together with the emergence of successful helicopters, all but extinguished interest in the autogiro.[br]Principal Honours and DistinctionsDaniel Guggenheim Medal. Royal Aeronautical Society Silver Medal, Gold Medal (posthumously) 1937.Bibliography1931, Wings of To-morrow: The Story of the Autogiro, New York (an early account of his work).He read a paper on his latest achievements at the Royal Aeronautical Society on 15 March 1935.Further ReadingP.W.Brooks, 1988, Cierva Autogiros: The Development of Rotary Wing Flight, Washington, DC (contains a full account of Cierva's work).Jose Warleta. 1977, Autogiro: Juan de la Cierva y su obra, Madrid (a detailed account of his work in Spain).Oliver Stewart, 1966, Aviation: The Creative Ideas, London (contains a chapter on Cierva).JDS -
2 Stibitz, George R.
SUBJECT AREA: Electronics and information technology[br]b. 20 April 1904 York, Pennsylvania, USA[br]American mathematician responsible for the conception of the Bell Laboratories "Complex " computer.[br]Stibitz spent his early years in Dayton, Ohio, and obtained his first degree at Denison University, Granville, Ohio, his MS from Union College, Schenectady, New York, in 1927 and his PhD in mathematical physics from Cornell University, Ithaca, New York, in 1930. After working for a time for General Electric, he joined Bell Laboratories to work on various communications problems. In 1937 he started to experiment at home with telephone relays as the basis of a calculator for addition, multiplication and division. Initially this was based on binary arithmetic, but later he used binary-coded decimal (BCD) and was able to cope with complex numbers. In November 1938 the ideas were officially taken up by Bell Laboratories and, with S.B.Williams as Project Manager, Stibitz built a complex-number computer known as "Complex", or Relay I, which became operational on 8 January 1940.With the outbreak of the Second World War, he was co-opted to the National Defence Research Council to work on anti-aircraft (AA) gun control, and this led to Bell Laboratories Relay II computer, which was completed in 1943 and which had 500 relays, bi-quinary code and selfchecking of errors. A further computer, Relay III, was used for ballistic simulation of actual AA shell explosions and was followed by more machines before and after Stibitz left Bell after the end of the war. Stibitz then became a computer consultant, involved in particular with the development of the UNIVAC computer by John Mauchly and J.Presper Eckert.[br]Principal Honours and DistinctionsInstitute of Electrical and Electronics Engineers Emanuel R.Priore Award 1977.Bibliography1957, with J.A.Larrivee, Mathematics and Computers, New York: McGraw-Hill. 1967, "The Relay computer at the Bell Laboratories", Datamation 35.Further ReadingE.Loveday, 1977, "George Stibitz and the Bell Labs Relay computer", Datamation 80. M.R.Williams, 1985, A History of Computing Technology, London: Prentice-Hall.KF
См. также в других словарях:
BCD — [Abk. für Binary Coded Decimal, dt. »binär kodierter Dezimalwert«], ein nach DIN 44 300 genormtes Verfahren zur Kodierung von Dezimalzahlen. Jede Stelle einer Dezimalzahl wird separat als Binärzahl (Zahl im Zweiersystem) dargestellt, wobei… … Universal-Lexikon
Bcd — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. {{{image}}} Sigles d une seule lettre Sigles de deux lettres > Sigles de trois lettres … Wikipédia en Français
BCD — is an acronym with multiple meanings, including: * Bad Conduct Discharge, a form of discharge from US military service * Bachelor of Community Design, a three year university degree offered at Dalhousie University * Barrels per calendar day, a… … Wikipedia
BCD — steht für: Binary Coded Decimal, englisch für „binär kodierte Dezimalzahl“ Bipolar, CMOS und DMOS, eine Silizium Mischtechnologie für integrierte Schaltungen, die bipolare, MOSFET und Hochvolt MOSFET Transistoren (DMOS Leistungs MOSFET)… … Deutsch Wikipedia
Bcd — steht für: Binary Coded Decimal, englisch für „binär kodierte Dezimalzahl“ Bipolar, CMOS und DMOS, eine Silizium Mischtechnologie für integrierte Schaltungen, die bipolare, MOSFET und Hochvolt MOSFET Transistoren (DMOS Leistungs MOSFET)… … Deutsch Wikipedia
BCD — sigla ES ingl. Binary Coded Decimal, notazione decimale codificata in binario, sistema di codifica … Dizionario italiano
BCD — I. noun Etymology: binary coded decimal Date: circa 1962 a system of writing numbers in which each decimal digit is represented by its 4 digit binary equivalent < 51 in BCD is 0101 0001 > II. abbreviation bad conduct discharge … New Collegiate Dictionary
BCD — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. Sigles d’une seule lettre Sigles de deux lettres > Sigles de trois lettres Sigles de quatre lettres … Wikipédia en Français
BCD — n. Computing a code representing decimal numbers as a string of binary digits. Etymology: abbr. for binary coded decimal * * * I. abbreviation bad conduct discharge II. ˌbē(ˌ)sēˈdē noun ( s) Etymology: binary … Useful english dictionary
BCD Holdings — Rechtsform N.V. Gründung 3. Januar 2006 Sitz Utrecht, Niederlande Leitung Joop Drechsel (CEO) Mitarbeiter 13 … Deutsch Wikipedia
BCD-Code — Stellenzahl 4 bewertbar ja stetig nein Gewicht 3 Maximaldistanz 4 Hamming Abstand … Deutsch Wikipedia
