Search results
Results From The WOW.Com Content Network
In this particular example, because the output is 90 degrees out of phase from the input, the Lissajous curve is a circle, and is rotating counterclockwise. When the input to an LTI system is sinusoidal, the output is sinusoidal with the same frequency, but it may have a different amplitude and some phase shift .
The government has published Bowditch ever since. George Blunt died in 1878. Nathaniel Bowditch continued to correct and revise the book until his death in 1838. Upon his death, the editorial responsibility for The New American Practical Navigator passed to his son, J. Ingersoll Bowditch. Very few significant changes were made under him.
The original intention of "dead" in the term is generally assumed to mean using a stationary object that is "dead in the water" as a basis for calculations. Additionally, at the time the first appearance of "dead reckoning", "ded" was considered a common spelling of "dead". This potentially led to later confusion of the origin of the term. [1]
Nathaniel Bowditch (March 26, 1773 – March 16, 1838) was an early American mathematician remembered for his work on ocean navigation.He is often credited as the founder of modern maritime navigation; his book The New American Practical Navigator, first published in 1802, is still carried on board every commissioned U.S. Naval vessel.
Two sample pages of the 2002 Nautical Almanac published by the U.S. Naval Observatory. A nautical almanac is a publication describing the positions of a selection of celestial bodies for the purpose of enabling navigators to use celestial navigation to determine the position of their ship while at sea.
Control point — The primary/base control used for preliminary measurements; it may consist of any known point capable of establishing accurate control of distance and direction (i.e. coordinates, elevation, bearings, etc.).
Buys Ballot's law first appeared in early versions (prior to 1900) of Bowditch's American Practical Navigator and other publications written to assist in passage planning and the safe conduct of ships at sea and is still included today both in Bowditch and in Sailing Directions (see following reference) as an item of practical reference and ...
"Lunars" or lunar distances were an early proposal for the calculation of longitude, having been first made practical by Regiomontanus in his 1474 Ephemerides Astronomicae. This almanac is one of the sources used by Amerigo Vespucci in his landmark longitude calculations he made on August 23, 1499 and September 15, 1499 as he explored South ...