DeLorme Street Atlas USA 2009, Руководство пользователя

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Getting Started
13
Glossary Terms
ADT
Alaska Daylight Time
Almanac
Data downloaded from satellites that contains the identity codes, location, and time
information for each satellite.
Arctic Circle
Parallel, or line of latitude around the Earth, at approximately 66°30' N. Because of
the Earth's inclination of about 23 1/2° to the vertical, it marks the southern limit of
the area within which, for one day or more each year, the Sun does not set (about
June 21) or rise (about December 21).
AST
Alaska Standard Time
Average Grade
Average of the grade from the start to the current cursor position (or finish).
Azimuth
The direction of travel or the direction between two points in reference to true or
magnetic north. When expressed in degrees, its value ranges from 0 to 360. A
compass heading is an azimuth. In most places, the word bearing has grown to
mean the same thing as azimuth. However, azimuth is always measured from true or
magnetic north in a clockwise direction. For example, due east is 90 and due west is
270. See also, Bearing.
Bearing
Like an azimuth, a bearing is measured in reference to true or magnetic north, but
its value never goes over 90. A bearing is always measured from the cardinal
directions of north or south. A typical bearing would be N45 E, which is the same as
an azimuth of 45. The bearing S45 W is an azimuth of 225. The use of the word
bearing has changed over the years and now means the same as azimuth. When
tracking, bearing displays the direction of travel between your current position and
your next waypoint, relative to true or magnetic North.
Bread crumb trail
A set of dots that display on your computer screen to record your progress as you
travel.
CDT
Central Daylight Time