Search results
Results from the WOW.Com Content Network
FreeRADIUS is a modular, high performance free RADIUS suite developed and distributed under the GNU General Public License, version 2, and is free for download and use.The FreeRADIUS Suite includes a RADIUS server, a BSD-licensed RADIUS client library, a PAM library, an Apache module, and numerous additional RADIUS related utilities and development libraries.
The Earth-centered, Earth-fixed coordinate system (acronym ECEF), also known as the geocentric coordinate system, is a cartesian spatial reference system that represents locations in the vicinity of the Earth (including its surface, interior, atmosphere, and surrounding outer space) as X, Y, and Z measurements from its center of mass.
Earth radius (denoted as R 🜨 or R E) is the distance from the center of Earth to a point on or near its surface. Approximating the figure of Earth by an Earth spheroid (an oblate ellipsoid), the radius ranges from a maximum (equatorial radius, denoted a) of nearly 6,378 km (3,963 mi) to a minimum (polar radius, denoted b) of nearly 6,357 km (3,950 mi).
Online maps can be basically divided by the covered area (global or local) and by the representation of this area (classic drawn or orthophoto). Global online maps [ edit ] These maps cover the world, but may have insufficient details in some areas.
The concept was originally popularized by a map posted on Reddit in 2013, made by a Texas ESL teacher named Ken Myers, whose username on the site gave the figure its name. [4] Myers's original circle covers only about 10% of the Earth's total surface area, with a radius of around 4,000 kilometers (2,500 miles), centered in the South China Sea. [1]
Formulas for the Web Mercator are fundamentally the same as for the standard spherical Mercator, but before applying zoom, the "world coordinates" are adjusted such that the upper left corner is (0, 0) and the lower right corner is ( , ): [7] = ⌊ (+) ⌋ = ⌊ ( [ (+)]) ⌋ where is the longitude in radians and is geodetic latitude in radians.
The Libre Map Project is an online collection of all digital USGS 1:24K scale topographic maps (as well as various other GIS data) covering the United States, available as a free download. History [ edit ]
Visualization of a celestial sphere. In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth.All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, which may be centered on Earth or the observer.