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Today's featured article Otto Julius Zobel (1887–1970) was a design engineer who worked for the American Telephone & Telegraph Company (AT&T) in the early part of the 20th century. Zobel's work on filter design was revolutionary and led, in conjunction with the work of John R. Carson, to significant commercial advances for AT&T in the field of frequency division multiplex (FDM) telephone transmissions. Although much of Zobel's work has been superseded by more modern filter designs, it remains the basis of filter theory and his papers are still referenced today. Zobel invented the m-derived filter and the constant-resistance filter, which remains in use. Zobel and Carson helped to establish the nature of noise in electric circuits, concluding that—contrary to mainstream belief—it is not even theoretically possible to filter out noise entirely and that noise will always be a limiting factor in what it is possible to transmit. Thus, they anticipated the later work of Claude Shannon, who showed how the theoretical information rate of a channel is related to the noise of the channel. (more...) Recently featured: Nebula Science Fiction – Australian Cattle Dog – Warkworth Castle Did you know... From Wikipedia's newest content: ... that three Chartists held at Monmouth County Gaol (pictured) were sentenced at the Shire Hall to be hanged, drawn and quartered in 1840? ... that the pilot episode of The Firm begins with a frenetic chase scene followed by a flashback to six weeks prior? ... that Norwegian newspaper editor Christian Friele was an honorary member of the Conservative Press Association, despite not attending any of its meetings? ... that prothrombin G20210A carriers who take oral contraceptives are at a 15-fold increased risk of developing blood clots in their veins (venous thrombosis)? ... that Mr. Basketball USA winners have been determined retroactively going back to 1955? ... that because he believed the American government had been infiltrated by communists, one young US Marine discharged himself from the officer training program and joined the Rhodesian Security Forces instead?

In the news The European Union imposes an embargo on future oil contracts with Iran. British novelist Salman Rushdie (pictured) cancels an appearance at the Jaipur Literature Festival in India, and four other writers leave the city after reading excerpts from The Satanic Verses, which is banned in the country. In a binding referendum, Croatian voters approve the country's proposed accession to the European Union. Boko Haram claims responsibility for a series of attacks in northern Nigeria that killed 185 people, two weeks after a similar set of assaults. American singer Etta James dies at the age of 73. On this day... January 28 98 – Trajan, namesake of a forum, a market and a column in Rome, succeeded his adoptive father Nerva as Roman emperor. 1813 – The novel Pride and Prejudice by English author Jane Austen (pictured) was published, using material from an unpublished manuscript that she originally wrote between 1796 and 1797. 1933 – Choudhry Rahmat Ali published a pamphlet entitled "Now or Never" in which he called for the creation of a Muslim state in northwest India that he termed "Pakstan". 1964 – An unarmed US Air Force T-39 Sabreliner on a training mission was shot down over Erfurt, East Germany, by a Soviet MiG-19, killing all three aboard. 1984 – Tropical Storm Domoina made landfall in southern Mozambique, causing some of the most severe flooding so far recorded in the region. More anniversaries: January 27 – January 28 – January 29 It is now January 28, 2012 (UTC) – Refresh this page

Today's featured picture View the animation Non-uniform rational B-spline is a mathematical model commonly used in computer graphics for generating and representing curves and surfaces for both analytic (described by mathematical formulas) and modeled shapes. Control points (shown as small spheres) influence the directions the surface takes. The square at the bottom sets the maximum width and length of the surface. Image: Greg L Recently featured: Grapefruit – Cologne panorama – Pixie's parasol mushroom

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