THE BELL SYSTEM Reprinted from The Bell System Technical Journal, Vol. XXVII, pp. 510588, 1948. Copyright 1948, AT T. All rights reserved. Reprinted with permission. The Evolution of the Quartz Crystal Clock* THE http://www.ieee-uffc.org/freqcontrol/marrison/Marrison.html
Extractions: The Evolution of the Quartz Crystal Clock* By WARREN A. MARRISON THE EPOCH OF CONTINUOUS FLOW THE EPOCH OF APERIODIC CONTROL THE EPOCH OF RESONANT CONTROL THE EVOLUTION OF ELECTRIC OSCILLATOR CLOCKS ... REFERENCES Since that period there has been a continuous use and improvement of timekeeping methods and devices, following sometimes quite independent lines, but developing through a long series of new ideas and refinements into the very precise means at our disposal today. The art of timekeeping and time measurement is of very great value, both from its direct social use in permitting time tables and schedules to be made, and in its relation to other arts and the sciences in which the measurement of rate and duration assume ever increasing importance. The early history of timekeeping was concerned almost entirely with the first of these and for many centuries the chief purpose of timekeeping devices was to provide means for the approximate subdivision of the day, particularly of the daylight hours. The most obvious events marking the passage of time were the rising and setting of the sun and its continuous apparent motion from east to west through the sky. The first practical measure of the position of the sun of which any record is known was the position or the length of shadows of fixed objects, resulting through a long period of development in the well-known sundial in its many forms. But the sundial was in no sense an instrument of precision and in no sense could be considered as a time
BNM-SYRTE - L'HORLOGE PARLANTE préconise la technique du film parlant, une methode simple pour réaliser la http://opdaf1.obspm.fr/www/hp.html
Extractions: Físico alemán que demostró experimentalmente que no hay ningún conductor eléctrico perfecto, pues todos oponen algo de resistencia. Ley del Ohm , publicada en su libro: « Die galvanische Kette, mathematisch bearbeitet » (1827): El voltaje es directamente proporcional a la intensidad, por la resistencia de un circuito: V=I.R
Extractions: en 1956 elle fit une apparition remarquée dans le film 'Giant' (Géant) avec James Dean en 1963, elle interprèta le rôle principal dans le film 'Cléopatre' le 15 mars 1964 elle épousa l'acteur Richard Burton à Montréal, 5e mariage pour Taylor et le 2e pour Burton, ils divorcèrent le 31 juillet 1973 en 1966, elle interprèta le rôle de 'Martha' dans le film 'Qui a peur de Virginia Woolf?' en 1994, elle tourna son dernier film 'The Flintstones'
Alliage présentation de Hubert Curien, numéro 1, pp. http://www.tribunes.com/tribune/alliage/auteurs.htm
Scienze: Macchine della macchina. Se poi siete affascinati dalla misura del http://www.url.it/ambienti/scienze/macchin/orologio.htm
Extractions: Earliest Known Uses of Some of the Words of Mathematics (Q) Last revision: May 20, 2004 Q. E. D. Euclid (about 300 B. C.) concluded his proofs with hoper edei deiksai, which Medieval geometers translated as quod erat demonstrandum ("that which was to be proven"). According to Veronika Oberparleiter, the earliest known use in print of the phrase quod erat demonstrandum in a Euclid translation appears in the translation by Bartholemew Zamberti published in Venice in 1505. In Dialogues Concerning Two New Sciences (1638) in Latin Galileo used quod erat intentum, quod erat demonstrandum, quod erat probandum, quod erat ostendendum, quod erat faciendum, quod erat determinandum, and quod erat propositum. In 1665 Benedictus de Spinoza (1632-1677) wrote a treatise on ethics, Ethica More Geometrico Demonstrata, in which he proved various moral propositions in a geometric manner. He wrote the abbreviation Q. E. D., as a seal upon his proof of each ethical proposition. Isaac Barrow used quod erat demonstrandum, quod erat faciendum (Q. E. F.), quod fieri nequit (Q. F. N.), and quod est absurdum (Q. E. A.). Isaac Newton used the abbreviation Q. E. D.
Earliest Known Uses Of Some Of The Words Of Mathematics (Q) theory (OED2). The term QUASIPERIODIC FUNCTION was introduced by ErnestEsclangon (1876-1954) (DSB, article Bohl). The term QUATERNION http://mail.mcjh.kl.edu.tw/~chenkwn/mathword/q.html
Extractions: Last revision: Aug. 2, 1999 Q. E. D. Euclid (about 300 B. C.) concluded his proofs with hoper edei deiksai, which Medieval geometers translated as quod erat demonstrandum ("that which was to be proven"). In 1665 Benedictus de Spinoza (1632-1677) wrote a treatise on ethics, Ethica More Geometrico Demonstrata, in which he proved various moral propositions in a geometric manner. He wrote the abbreviation Q. E. D., as a seal upon his proof of each ethical proposition. The Q. E. D. abbreviation was also used by Isaac Newton in the Principia, by Galileo in a Latin text, and by Isaac Barrow, who additionally used quod erat faciendum (Q. E. F.), quod fieri nequit (Q. F. N.), and quod est absurdum (Q. E. A.). [Martin Ostwald, Sam Kutler, Robin Hartshorne, David Reed] QUADRANGLE is found in English in the fifteenth century. The word was later used later by Shakespeare. QUADRATIC is derived from the Latin quadratus, meaning "square." In English, quadratic was used in 1668 by John Wilkins (1614-1672) in An essay towards a real character, and a philosophical language
1932 - Wikipédia ErnestEsclangon invente les horloges parlantes. Sports. 4 février http://fr.wikipedia.org/wiki/1932
