The simplest mathematical method to estimate tortuosity is the arc-chord ratio: the ratio of the length of the curve (L) to the distance between the ends of it (C): Arc-chord ratio equals 1 for a straight line and is infinite for a circle.
ERS is a set of computer programs set to run in a specified order on the UNISYS Mainframe at the Enterprise. Computing Center in Martinsburg, West Virginia and the Enterprise Computing Center in Memphis, (ECC-MTB and. ECC-MEM) Tennessee. All ERS information is housed on the ERS database at each computing center.
Erlang is a general-purpose programming language and runtime environment. Erlang has built-in support for concurrency, distribution and fault tolerance. Erlang is used in several large telecommunication systems from Ericsson. Erlang is available as open source from http://www.erlang.org.