Topic: Maps

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🔗 Yahoo Pipes

🔗 Internet 🔗 Software 🔗 Software/Computing 🔗 Maps

Yahoo! Pipes was a web application from Yahoo! that provided a graphical user interface for building data mashups that aggregate web feeds, web pages, and other services, creating Web-based apps from various sources, and publishing those apps. The application worked by enabling users to "pipe" information from different sources and then set up rules for how that content should be modified (for example, filtering). Other than the pipe editing page, the website had a documentation page and a discussion page. The documentation page contained information about pipes including guides for the pipe editor and troubleshooting. The discussion page enabled users to discuss the pipes with other users.

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🔗 Coastline Paradox

🔗 Mathematics 🔗 Maps

The coastline paradox is the counterintuitive observation that the coastline of a landmass does not have a well-defined length. This results from the fractal curve-like properties of coastlines, i.e., the fact that a coastline typically has a fractal dimension (which in fact makes the notion of length inapplicable). The first recorded observation of this phenomenon was by Lewis Fry Richardson and it was expanded upon by Benoit Mandelbrot.

The measured length of the coastline depends on the method used to measure it and the degree of cartographic generalization. Since a landmass has features at all scales, from hundreds of kilometers in size to tiny fractions of a millimeter and below, there is no obvious size of the smallest feature that should be taken into consideration when measuring, and hence no single well-defined perimeter to the landmass. Various approximations exist when specific assumptions are made about minimum feature size.

The problem is fundamentally different from the measurement of other, simpler edges. It is possible, for example, to accurately measure the length of a straight, idealized metal bar by using a measurement device to determine that the length is less than a certain amount and greater than another amount—that is, to measure it within a certain degree of uncertainty. The more accurate the measurement device, the closer results will be to the true length of the edge. When measuring a coastline, however, the closer measurement does not result in an increase in accuracy—the measurement only increases in length; unlike with the metal bar, there is no way to obtain a maximum value for the length of the coastline.

In three-dimensional space, the coastline paradox is readily extended to the concept of fractal surfaces whereby the area of a surface varies, depending on the measurement resolution.

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🔗 The China GPS shift problem

🔗 China 🔗 Maps

Due to national security concerns, the use of geographic information in the People's Republic of China is restricted to entities that obtain a special authorization from the administrative department for surveying and mapping under the State Council. Consequences of the restriction include fines for unauthorized surveys, lack of geotagging information on many cameras when the GPS chip detects a location within China, incorrect alignment of street maps with satellite maps in various applications, and seeming unlawfulness of crowdsourced mapping efforts such as OpenStreetMap.

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🔗 Trap Street

🔗 Maps

In cartography, a trap street is a fictitious entry in the form of a misrepresented street on a map, often outside the area the map nominally covers, for the purpose of "trapping" potential copyright violators of the map who, if caught, would be unable to explain the inclusion of the "trap street" on their map as innocent. On maps that are not of streets, other "copyright trap" features (such as nonexistent towns, or mountains with the wrong elevations) may be inserted or altered for the same purpose.

Trap streets are often nonexistent streets; but sometimes, rather than actually depicting a street where none exists, a map will misrepresent the nature of a street in a fashion that can still be used to detect copyright violators but is less likely to interfere with navigation. For instance, a map might add nonexistent bends to a street, or depict a major street as a narrow lane, without changing its location or its connections to other streets.

Trap streets are rarely acknowledged by publishers. One known case is a popular driver's atlas for the city of Athens, Greece, which has a warning inside its front cover that potential copyright violators should beware of trap streets.

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🔗 The Boston Camera

🔗 Maps 🔗 Photography

The Boston Camera, also known as Pie Face and officially classified as the K-42 Camera Model, was a prototype airborne photo reconnaissance camera manufactured for the United States Air Force by Boston University in 1951 and tested on the Convair B-36 and the C-97 Stratofreighter. The model carried on the first ERB-36D (44-92088) had a 6,096-millimetre (240.0 in) focal length, which was achieved using a series of lenses and mirrors. The lens had an f/8 stop and used a 1/400 second shutter speed, and could photograph a golf ball from an altitude of 45,000 feet (14,000 m) feet. The camera used 18-by-36-inch (46 by 91 cm) negatives. The camera was installed aboard Boeing C-97A 49-2592 (not an "RC-97" or "EC-97" as often widely quoted) which was used operationally by the 7405th Support Squadron based at Wiesbaden, West Germany between 1952 and 1962. It was given to the Air Force Museum in 1964, along with a contact print of a golf ball on a course.

In the words of CIA historian Dino Brugioni:

The lens was designed in 1947 by Dr. James Baker for installation in a camera designed by the Boston University Optical Research Laboratory. The camera weighed about three tons, and eight hundred pounds of lead shot were required to balance it. Supposedly, it was first installed and test-flown in an RB-36, then installed as a left-looking oblique camera in an RC-97. The first photo Arthur Lundahl and I saw from this project was of New York City. The aircraft was seventy-two miles away, and yet we could see people in Central Park.

The Boston Camera was plagued with problems that caused it to vibrate and produce smearing on the newspaper-sized negative, so that photo interpreters would see several smeared frames along with several clear ones. It is currently displayed at the National Museum of the US Air Force in Dayton, Ohio.

From the display placard:

This camera, manufactured for the US Air Force by Boston University in 1951, is the largest aerial camera ever built. It was installed in an RB-36D in 1954 and tested for about a year. Later it was used in a C-97 aircraft flying along the air corridor through communist East Germany to Berlin, but a 10,000 ft (3,000 m) altitude restriction imposed by the communists made the camera less useful than at a higher altitude. It was also used on reconnaissance missions along the borders of Eastern European nations. The camera made an 18 x 36 inch negative and was so powerful a photo interpreter could detect a golf ball from an altitude of 45,000 feet (14,000 m). Dr. James Baker of Harvard University designed the camera.

Technical Notes:

Shutter Speed: 1/400 sec

Weight: 6,500 lbs (3 metric ton) (camera and aircraft mount)

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🔗 Hajnal line

🔗 Europe 🔗 Maps 🔗 Sociology

The Hajnal line is a border that links Saint Petersburg, Russia and Trieste, Italy. In 1965, John Hajnal discovered it divides Europe into two areas characterized by different levels of nuptiality. To the west of the line, marriage rates and thus fertility were comparatively low and a significant minority of women married late or remained single; to the east of the line and in the Mediterranean and select pockets of Northwestern Europe, early marriage was the norm and high fertility was countered by high mortality.

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🔗 Piri Reis Map

🔗 Maps 🔗 Turkey 🔗 Paranormal

The Piri Reis map is a world map compiled in 1513 by the Ottoman admiral and cartographer Piri Reis (pronounced [piːˈɾiː ɾeis]). Approximately one third of the map survives; it shows the western coasts of Europe and North Africa and the coast of Brazil with reasonable accuracy. Various Atlantic islands, including the Azores and Canary Islands, are depicted, as is the mythical island of Antillia and possibly Japan.

The map's historical importance lies in its demonstration of the extent of global exploration of the New World by approximately 1510, and in its claim to have used a map of Christopher Columbus, otherwise lost, as a source. Piri also stated that he had used ten Arab sources and four Indian maps sourced from the Portuguese. More recently, the map has been the focus of claims for the pre-modern exploration of the Antarctic coast.

The Piri Reis map is in the Library of the Topkapı Palace in Istanbul, Turkey, but is not usually on display to the public.

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🔗 An Atlas of Fantasy

🔗 Books 🔗 Maps

An Atlas of Fantasy, compiled by Jeremiah Benjamin Post, was originally published in 1973 by Mirage Press and revised for a 1979 edition by Ballantine Books. The 1979 edition dropped twelve maps from the first edition and added fourteen new ones. It also included an introduction by Lester del Rey.

To remain of manageable size, the Atlas excludes advertising maps, cartograms, most disproportionate maps, and alternate history ("might have been") maps, focusing instead on imaginary lands derived from literary sources. It purposefully omits "one-to-one" maps such as Thomas Hardy's Wessex (which merely renames places in southwest England), but includes Barsetshire and Yoknapatawpha County, which are evidently considered to be sufficiently fictionalized. The emphasis is on science fiction and fantasy, though Post suggests there exist enough mystery fiction maps to someday create The Detectives' Handy Pocket Atlas. Other maps were omitted due to permission costs or reproduction quality.

The maps are reproduced from many sources, and an Index of Artists is included.

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🔗 Mao Kun Map

🔗 China 🔗 Maps

Mao Kun map, usually referred to in modern Chinese sources as Zheng He's Navigation Map (simplified Chinese: 郑和航海图; traditional Chinese: 鄭和航海圖; pinyin: Zhèng Hé hánghǎi tú), is a set of navigation charts published in the Ming dynasty military treatise Wubei Zhi. The book was compiled by Mao Yuanyi in 1621 and published in 1628; the name of the map refers to his grandfather Mao Kun (Chinese: 茅坤; pinyin: Máo Kūn) from whose library the map is likely to have originated. The map is often regarded as a surviving document from the expeditions of Zheng He in addition to accounts written by Zheng's officers, such as Yingya Shenglan by Ma Huan, Xingcha Shenglan by Fei Xin, and Xiyang Fanguo Zhi by Gong Zhen. It is the earliest Chinese map to give an adequate representation of Southern Asia, Persia, Arabia and East Africa.

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🔗 Waldseemüller map

🔗 United States 🔗 Library of Congress 🔗 Geography 🔗 Maps 🔗 Libraries

The Waldseemüller map or Universalis Cosmographia ("Universal Cosmography") is a printed wall map of the world by German cartographer Martin Waldseemüller, originally published in April 1507. It is known as the first map to use the name "America". The name America is placed on what is now called South America on the main map. As explained in Cosmographiae Introductio, the name was bestowed in honor of the Italian Amerigo Vespucci.

The map is drafted on a modification of Ptolemy's second projection, expanded to accommodate the Americas and the high latitudes. A single copy of the map survives, presently housed at the Library of Congress in Washington, D.C.

Waldseemüller also created globe gores, printed maps designed to be cut out and pasted onto spheres to form globes of the Earth. The wall map, and his globe gores of the same date, depict the American continents in two pieces. These depictions differ from the small inset map in the top border of the wall map, which shows the two American continents joined by an isthmus.

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