Template:Selected anniversaries/September 22: Difference between revisions
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||1897: Charles Stuart Ballantine born ... mathematical physicist and inventor. He discovered the "antenna effect" in coil-type systems and invented the capacity compensator for its control. In 1923 he was awarded the John Tyndall Fellowship in physics at Harvard University. At this time he developed the principle of negative feedback to stabilize and reduce distortion in transmission circuits, modulators, amplifiers, and detectors. Mr. Ballantine engaged in extensive studies of detection at high signal levels, fluctuation noise in radio receivers and tubes, development of technique for sound measurements of loudspeakers and receivers, microphone calibration, and broadcast receiver design. He invented a method of stabilizing radio-frequency amplifiers by means of a Wheatstone-bridge circuit, and in 1929 made important contributions to the design and use of vacuum tubes for radio receiving sets, later improving condenser microphones in such a way as to permit increased fidelity in the transmission of sound programs. One of the most widely known of his many contributions to radio was his invention of the first "throat microphone" to pick up voice sounds directly from the larynx, a device of major importance to aviators, later widely used by the Army Air Force. Pic: https://ethw.org/Charles_Stuart_Ballantine | ||1897: Charles Stuart Ballantine born ... mathematical physicist and inventor. He discovered the "antenna effect" in coil-type systems and invented the capacity compensator for its control. In 1923 he was awarded the John Tyndall Fellowship in physics at Harvard University. At this time he developed the principle of negative feedback to stabilize and reduce distortion in transmission circuits, modulators, amplifiers, and detectors. Mr. Ballantine engaged in extensive studies of detection at high signal levels, fluctuation noise in radio receivers and tubes, development of technique for sound measurements of loudspeakers and receivers, microphone calibration, and broadcast receiver design. He invented a method of stabilizing radio-frequency amplifiers by means of a Wheatstone-bridge circuit, and in 1929 made important contributions to the design and use of vacuum tubes for radio receiving sets, later improving condenser microphones in such a way as to permit increased fidelity in the transmission of sound programs. One of the most widely known of his many contributions to radio was his invention of the first "throat microphone" to pick up voice sounds directly from the larynx, a device of major importance to aviators, later widely used by the Army Air Force. Pic: https://ethw.org/Charles_Stuart_Ballantine | ||
||1900: Paul Hugh Emmett born ... chemist and engineer. Manhattan Project. Pic search | ||1900: Paul Hugh Emmett born ... chemist and engineer. Manhattan Project. Pic search. | ||
File:Maurice d'Ocagne.jpg|link=Philbert Maurice d’Ocagne (nonfiction)|1900: Mathematician, engineer, and [[Gnomon algorithm]] researcher [[Philbert Maurice d’Ocagne (nonfiction)|Philbert Maurice d’Ocagne]] invents a [[Nomogram (nonfiction)|nomogram]] which detects the [[Forbidden Ratio]]. | File:Maurice d'Ocagne.jpg|link=Philbert Maurice d’Ocagne (nonfiction)|1900: Mathematician, engineer, and [[Gnomon algorithm]] researcher [[Philbert Maurice d’Ocagne (nonfiction)|Philbert Maurice d’Ocagne]] invents a [[Nomogram (nonfiction)|nomogram]] which detects the [[Forbidden Ratio]]. | ||
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||1918: Charles Duncan Michener born ... entomologist ... leading expert on bees, his magnum opus being ''The Bees of the World''. Michener's work on social evolution in the Halictidae in the 1960s helped set the stage for the sociobiology revolution of the 1970s, with E. O. Wilson relying to a great degree on Michener's concepts regarding the paths from solitary to highly social life. Pic. | ||1918: Charles Duncan Michener born ... entomologist ... leading expert on bees, his magnum opus being ''The Bees of the World''. Michener's work on social evolution in the Halictidae in the 1960s helped set the stage for the sociobiology revolution of the 1970s, with E. O. Wilson relying to a great degree on Michener's concepts regarding the paths from solitary to highly social life. Pic. | ||
||1921: Theoretical chemist and academic Robert Parr born. Working with DuPont chemist Rudolph Pariser, Parr developed a method of computing approximate molecular orbitals for pi electron systems, published in 1953. Since an identical procedure was derived by John A. Pople the same year, it is generally referred to as the Pariser-Parr-Pople method or PPP method. The PPP method differed from existing structural chemistry thinking by advancing the concept of zero differential overlap approximation. Pic search | ||1921: Theoretical chemist and academic Robert Parr born. Working with DuPont chemist Rudolph Pariser, Parr developed a method of computing approximate molecular orbitals for pi electron systems, published in 1953. Since an identical procedure was derived by John A. Pople the same year, it is generally referred to as the Pariser-Parr-Pople method or PPP method. The PPP method differed from existing structural chemistry thinking by advancing the concept of zero differential overlap approximation. Pic search. | ||
||1927: Jack Dempsey loses the "Long Count" boxing match to Gene Tunney. | ||1927: Jack Dempsey loses the "Long Count" boxing match to Gene Tunney. | ||
||1937: Nicolae Popescu born ... mathematician and Emeritus Professor. Pic search | ||1937: Nicolae Popescu born ... mathematician and Emeritus Professor. Pic search. | ||
||1954: BARK (Swedish: Binär Aritmetisk (Automatisk) Relä-Kalkylator, lit. 'Binary Arithmetic (Automatic) Relay Calculator') taken offline. BARK was an early electromechanical computer, built using standard telephone relays, implementing a 32-bit binary machine. Pic. | ||1954: BARK (Swedish: Binär Aritmetisk (Automatisk) Relä-Kalkylator, lit. 'Binary Arithmetic (Automatic) Relay Calculator') taken offline. BARK was an early electromechanical computer, built using standard telephone relays, implementing a 32-bit binary machine. Pic. | ||
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||1979: A bright flash, resembling the detonation of a nuclear weapon, is observed near the Prince Edward Islands. Its cause is never determined. | ||1979: A bright flash, resembling the detonation of a nuclear weapon, is observed near the Prince Edward Islands. Its cause is never determined. | ||
||1979: Charles Ehresmann dies ... mathematician who worked in differential topology and category theory. He was an early member of the Bourbaki group, and is known for his work on the differential geometry of smooth fiber bundles, notably the Ehresmann connection, the concept of jets of a smooth map, and his seminar on category theory. | ||1979: Charles Ehresmann dies ... mathematician who worked in differential topology and category theory. He was an early member of the Bourbaki group, and is known for his work on the differential geometry of smooth fiber bundles, notably the Ehresmann connection, the concept of jets of a smooth map, and his seminar on category theory. Pic. | ||
||1990: Operation Steel Box ends: a joint U.S.-West German operation which moved 100,000 U.S. chemical weapons from Germany to Johnston Atoll. Pic. | ||1990: Operation Steel Box ends: a joint U.S.-West German operation which moved 100,000 U.S. chemical weapons from Germany to Johnston Atoll. Pic. | ||
||1991: The Dead Sea Scrolls are made available to the public for the first time by the Huntington Library. | ||1991: The Dead Sea Scrolls are made available to the public for the first time by the Huntington Library. | ||
||2000: Mathematician and academic Alexei Kostrikin born. He will specialize in algebra and algebraic geometry, making important contributions to the Burnside problem; he also wrote widely used textbooks. Pic search | ||2000: Mathematician and academic Alexei Kostrikin born. He will specialize in algebra and algebraic geometry, making important contributions to the Burnside problem; he also wrote widely used textbooks. Pic search. | ||
||2001: Leslie Howarth dies ... mathematician who dealt with hydrodynamics and aerodynamics. Pic: http://rsbm.royalsocietypublishing.org/content/roybiogmem/55/107.full.pdf | ||2001: Leslie Howarth dies ... mathematician who dealt with hydrodynamics and aerodynamics. Pic: http://rsbm.royalsocietypublishing.org/content/roybiogmem/55/107.full.pdf | ||
Revision as of 06:17, 19 April 2020
1547: Philologist, mathematician, astronomer, and poet Philipp Nicodemus Frischlin born. His prolific and versatile genius will produce a great variety of works, but his reckless life and libelous letters will lead to imprisonment.
1624: Math photographer Cantor Parabola captures unprecedented images of Renaissance-era crimes against mathematical constants.
1703: Mathematician and scientist Vincenzo Viviani dies. In 1660, Viviani and Giovanni Alfonso Borelli conducted an experiment to determine the speed of sound. Timing the difference between the seeing the flash and hearing the sound of a cannon shot at a distance, they calculated a value of 350 meters per second (m/s), considerably better than the previous value of 478 m/s obtained by Pierre Gassendi.
1900: Mathematician, engineer, and Gnomon algorithm researcher Philbert Maurice d’Ocagne invents a nomogram which detects the Forbidden Ratio.
1970: Physician, research scientist, and author Alice Hamilton dies. She was a leading expert in the field of occupational health and a pioneer in the field of industrial toxicology.
1974: Physicist Winfried Otto Schumann dies. He predicted the existence of Schumann resonances, a series of low-frequency resonances caused by lightning discharges in the atmosphere.
1976: Mathematician and crime-fighter Shoshichi Kobayashi uses transformation groups of geometric structures to detect and prevent crimes against mathematical constants.
2012: Mathematician, author, activist, and academic Irving Adler dies. He was a plaintiff in the McCarthy-era case Adler vs. Board of Education.
2013: Signed first edition of Skip Digits, Conductor stolen; US Treasury investigators say money trail leads to Baron Zersetzung.
2014: The MAVEN probe reaches Mars and is inserted into an areocentric elliptic orbit 6,200 km (3,900 mi) by 150 km (93 mi) above the planet's surface.
2016: Two Creatures 2 is declared Picture of the Day by the citizens of New Minneapolis, Canada.
2017: Dennis Paulson celebrates third anniversary the MAVEN probe reaching Mars.