Harry Nyquist - Harry Nyquist Harry Nyquist (February 7, 1889 - April 4, 1976) was an important contributor to information theory. He was born in Nilsby, Sweden. He emigrated to the USA in 1907 and entered the University of North Dakota in 1912. He received a Ph.D. in physics at Yale University in 1917. He worked at AT&T from 1917 to 1934, then moved to Bell Telephone Laboratories. As an engineer at Bell Laboratories, he did important work on thermal noise ("Johnson-Nyquist noise") and the stability of feedback amplifiers. His early theoretical work on determining the bandwidth requirements for transmitting information, as published in "Certain factors affecting telegraph speed" (Bell System Technical Journal, 3, 324-346, 1924), laid the foundations for later advances by Claude Shannon, which led to the.
Johnson-Nyquist noise - Johnson-Nyquist noise Johnson-Nyquist noise (sometimes only "Nyquist noise") is the equilibrium fluctuations of the electric current inside an electrical conductor, which happen without any applied voltage, due to the random thermal motion of the charge carriers (the electrons). It is to be distinguished from Shot noise, which describes the additional current fluctuations that occur when a voltage is applied and a macroscopic current starts to flow. The strength of Nyquist noise is related to the temperature and the resistance of the conductor. See: Harry Nyquist, J. Johnson J. Johnson, "Thermal Agitation of Electricity in Conductors", Phys. Rev. 32, 97 (1928) -- the experiment H. Nyquist, "Thermal Agitation of Electric Charge in Conductors", Phys. Rev. 32, 110 (1928) -- the theory.
Nyquist-Shannon sampling theorem - Nyquist-Shannon sampling theorem The Nyquist-Shannon sampling theorem is a fundamental tenet in the field of information theory, in particular telecommunications. The theorem states that, when converting from an analog signal to digital (or otherwise sampling a signal at discrete intervals), the sampling frequency must be greater than twice the highest frequency of the input signal in order to be able to reconstruct the original perfectly from the sampled version. If the sampling frequency is less than this limit, then frequencies in the original signal that are above half the sampling rate will be "aliased" and will appear in the resulting signal as lower frequencies. Therefore, an analog low-pass filter is typically applied before sampling to ensure that no components with frequencies greater than half the sample.
Nyquist plot - Nyquist plot A Nyquist plot is a type of graph used in signal processing in which the magnitude and phase of a frequency response are plotted on orthogonal axes. This plot combines the two types of Bode plot - magnitude and phase - on a single graph, with frequency as a parameter along the curve. It is useful for assessing the stability of a system with feedback. The Nyquist plot shows the amplification/attenuation and phase-shift of the signal in the complex plane. The phase-shift of a signal with frequency ω is represented by the argument and the magnitude is represented by the length of a vector from the origin in the direction described by the argument. The Nyquist plot is very useful in looking at the.
Information theory - subject to a fidelity criterion. These two wings of information theory are joined together and mutually justified by the information transmission theorems, or source-channel separation theorems that justify the use of bits as the universal currency for information in many contexts. It is generally accepted that the modern discipline of information theory began with the publication by Claude E. Shannon of his article "The Mathematical Theory of Communication" in the Bell System Technical Journal in July and October of 1948. This work drew on earlier publications by Harry Nyquist and Ralph Hartley. In the process of working out a theory of communications that could be applied by electrical engineers to design better telecommunications systems, Shannon defined a measure of entropy: that, when applied to an information source, could determine the capacity.
Timeline of thermodynamics, statistical mechanics, and random processes - perturbation 1893 - Wilhelm Wien discovers the displacement law for a blackbody's maximum specific intensity 1905 - Albert Einstein mathematically analyzes the Brownian motion 1906 - Walther Nernst presents a formulation of the third law of thermodynamics 1910 - Albert Einstein and Marian Smoluchowski find the Einstein-Smoluchowski formula for the attenuation coefficient due to density fluctuations in a gas 1916 - Sydney Chapman and David Enskog systematically develop a kinetic theory of gases 1919 - James Jeans discovers that the dynamical constants of motion determine the distribution function for a system of particles 1920 - Meghnad Saha states his ionization equation 1923 - Peter Debye and Erich Huckel publish a statistical treatment of the dissociation of electrolytes 1928 - J.B. Johnson discovers Johnson noise in a resistor 1928 - Harry Nyquist.
List of mathematical topics (M-O) - Myhill-Nerode Theorem N N-body problem -- N-Mahlo cardinal -- N-sequence -- Naive Bayesian classification -- Naive set theory -- Napier -- Napier, John -- Napier's bones -- Nash embedding theorem -- Nash equilibrium -- Nash, John Forbes -- Natarajan Saradha -- Natural deduction -- Natural logarithm -- Natural number -- Natural numbers -- Natural transformation -- Navier-Stokes equations -- NC -- Nearest neighbour relation -- Necessary and sufficient -- Necker cube -- Negabinary -- Negative and non-negative numbers -- Negative binomial distribution -- Negative number -- Negligible set -- Neper -- Nernst equation Talk:Nernst equation -- Net (mathematics) -- Network topology -- Neumann, John von -- Neural network -- Nevanlinna, Rolf -- NewPGen -- Newcomb's paradox -- Newton, Isaac -- Newton-Cotes formulas -- Newtonian physics -- Newton polynomial -- Newton's method.
Harry S. Truman - Harry S. Truman Harry S. Truman President Truman in November 1945 Order: 33rd President Term of Office: April 12, 1945 - January 20, 1953 Followed: Franklin Delano Roosevelt Succeeded by: Dwight D. Eisenhower Date of Birth Tuesday, May 8, 1884 Place of Birth: Lamar, Missouri Date of Death: Tuesday, December 26, 1972 Place of Death: Kansas City, Missouri First Lady: Elizabeth "Bess" Virginia Wallace Profession: farmer Political Party: Democrat Vice President: Alben W. Barkley (1949-1953) Harry S#Truman's_middle_initial Truman (May 8, 1884 - December 26, 1972) was the thirty-fourth (1945) Vice President and the thirty-third (1945-1953) President of the United States, succeeding to the office upon the death of Franklin Roosevelt. Truman's presidency was very eventful, seeing the end of World War II, the beginning of the.
Harry Potter - Harry Potter Harry James Potter is a fictional character and protagonist of a series of fantasy novels by J. K. Rowling the first of which was released in 1997. The books are primarily aimed at children, but have fans of all ages. There is a series of films based directly on the books, the first of which was released in 2001. According to the author, the stories appeared in her head, fully formed, while she was on a train from Manchester to London. The sales from the books have, according to unsubstantiated rumours, made her richer than Queen Elizabeth II of the United Kingdom. Each book in the series chronicles one year in Harry's life at Hogwarts School of Witchcraft and Wizardry where he learns Magic..
Harry Connick, Jr. - Harry Connick, Jr. Harry Connick, Jr. (born September 11, 1967) is a singer, pianist and actor. His music encompasses jazz, some very much in the style of the crooners of the 1940's and early 50's, and blues. His father, Harry Connick, Sr is a lawyer who became district attorney of New Orleans and was indicted on corruption charges. Discography: 11 Harry Connick Jr 20 When Harry Met Sally (soundtrack) We Are In Love Blue Light, Red Light 25 30 When My Heart Finds Christmas She Star Turtle Come By Me To See You (others) Films: Memphis Belle (1990) Little Man Tate (1991) Copycat (1995) Indenpendece Day (1996) Hope Floats(1998) (others).
Harry Secombe - Harry Secombe Harry Secombe (September 8, 1921 - April 11, 2001) was a Welsh entertainer, with a fine tenor singing voice and a talent for comedy. He was one of the original Goons, appearing in the radio series as Neddy Seagoon, the protagonist of the show's ridiculous plots. He had first met Spike Milligan, the founder of the Goons, during army service in World War II in North Africa. Secombe appeared in many stage musicals, including Pickwick (1963) and The Four Musketeers (1967), and had several chart successes, the song most associated with him being "If I Ruled the World" (from Pickwick). He also appeared as Mr. Bumble in Lionel Bart's film Oliver! (1968). Later in life, Secombe (whose brother was a vicar) attracted new audiences.
Harry Shearer - Harry Shearer Harry Shearer (born December 23, 1943) is a comedic American actor and writer who began his career as a child actor in 1950s movies (The Robe) and TV (The Jack Benny Show). Shearer played Eddie Haskell in the pilot for the TV series, Leave it to Beaver. Shearer was later a member of Los Angeles radio comedy group The Credibility Gap, 1968 - 1974, and regular on Saturday Night Live in 1979 - 1980 and 1984 - 1985 seasons. Shearer co-created, co-wrote and co-starred in Rob Reiner's 1984 film This is Spinal Tap with Michael McKean and Christopher Guest; the three of them also collaborated on the acclaimed 2003 spoof "A Mighty Wind" Shearer is probably best-known for his astounding voiceover work on The.
Harry Enfield - Harry Enfield Harry Enfield is an English comedian who quickly came to prominence after appearing on Channel 4's Saturday Live in a number of different personae. These quickly entered the national consciousness. Amongst these characters was the Greek kebab-seller with markedly fractured English, "Stavros", a profound supporter of the football club Arsenal F.C, which he demonstrated by frequently uttering the phrase "Up the Arse". His other popular character "Loadsamoney" spawned a hit single in 1988. Before that he provided voices for the British satirical puppet show Spitting Image. After Saturday Live, Enfield moved to the BBC where he developed his sketch show, "Harry Enfield's Television Programme", and later Harry Enfield and Chums with fellow comedians Paul Whitehouse (later of Fast Show fame) and Kathy Burke. This.
Harry Truman (volcano victim) - Harry Truman (volcano victim) For the U.S. President, see Harry S. Truman Harry Truman (October 30, 1896 - May 18, 1980) came to brief fame as a well loved, if eccentric resident of Washington State who refused to leave the lodge he owned at the base of Mount St. Helens when warned that it was about to erupt. He was killed in the ensuing blast..
Harry Turtledove - Harry Turtledove Harry Turtledove (born June 14, 1949), is a historian and novelist who is best known for his alternate history fantasy and science fiction works. Turtledove was born in Los Angeles, California. After flunking out of his freshman year at Caltech, he attended UCLA, where he received a Ph.D. in Byzantine history in 1977. His dissertation was on The Immediate Successors of Justinian: A Study of the Persian Problem and of Continuity and Change in Internal Secular Affairs in the Later Roman Empire During the Reigns of Justin II and Tiberius II Constantine (A.D. 565-582). In 1979, Turtledove published his first two novels, Wereblood and Werenight, under the pseudonym "Eric G. Iverson". Turtledove later explained that his editor at Belmont Tower did not think people.
Harry Potter and the Philosopher's Stone - Harry Potter and the Philosopher's Stone Harry Potter and the Philosopher's Stone is the first volume in an ongoing series of (eventually) seven books for children written by British author J. K. Rowling, and starring Harry Potter, a young wizard. The book has also been made into a film of the same name. Both the book and film go by the name Harry Potter and the Sorcerer's Stone in the USA. Plot of the book When Harry Potter was 15 months old, the evil Lord Voldemort killed his parents and tried to kill Harry as well. Harry survived, but a scar remained on his forehead. He was sent to live with his abusive Aunt Petunia and Uncle Vernon. They forced him to live in a cupboard.
Harry Houdini - Harry Houdini Harry Houdini (March 24, 1874 - October 31, 1926) was the stage name of Ehrich Weiss (born Weiss Erik in the native Hungarian), one of the most famous magicians, escapologists and stunt performers of all time. Early Life Houdini was born on March 24 1874 in Budapest, Hungary. In 1878, his family emigrated to the United States. At first, they lived in Appleton, Wisconsin, where his father, Mayer Samuel Weiss, served as rabbi of the Zion Reform Jewish Congregation. After losing his tenure, Mayer moved to New York City with Ehrich in 1887, where they lived in a boarding-house on East Seventy-ninth Street. Mr. Weiss later called for the rest of his family to join him once he found more permanent housing. Career In.
Harry Palmer - Harry Palmer Harry Palmer is a fictional secret agent who is the central character in a number of films based on the writings of Len Deighton. (In Deighton's novels, the character is unnamed.) See also: The Ipcress File Harry Palmer founded and first franchised the Avatar self-development system courses later associated with Star's Edge. After working with Scientology, Palmer set up an more individual-based series of exercises..
Harry Paget Flashman - Harry Paget Flashman Harry Paget Flashman Fictional character originally created by the author Thomas Hughes, in his semi-autobiographical work Tom Brown's School Days first published in 1857. Tom Brown's School Days was set at Rugby School and Flashman is the notorious school bully, who persecutes the book's hero Tom Brown. George MacDonald Fraser had the conceit of writing a series of further fictional adventures of this coward and bully as he cuts a swathe through the wars and uproars (and the boudoirs and harems) of the 19th century. Though Flashman constantly betrays his friends, runs from danger, or hides cowering in fear, he arrives at the end of each book with medals, praise from the mighty, and the love of one or more beautiful and enthusiastic.
Harry Mulisch - Harry Mulisch Harry Mulisch (born July 29, 1927) is a Dutch author. He has written novels, plays, essays, poems, and philosophical reflections. Mulisch was born in Haarlem and has lived for many years in Amsterdam. A frequent theme in his work is the Second World War. Mulisch gained international recognition with the film De Aanslag, (1986) which was based on his eponymous book. It received an Oscar for best foreign movie. His novel De ontdekking van de Hemel (1992) was filmed in 2001 as The Discovery of Heaven..
