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. | ||1900: Paul Hugh Emmett born ... chemist and engineer. Manhattan Project. Pic search yes: https://www.google.com/search?q=Paul+Hugh+Emmett&oq=Paul+Hugh+Emmett | ||
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]]. | ||
Revision as of 06:28, 18 April 2019
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.