L-system

An L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar. An L-system consists of an alphabet of symbols that can be used to make strings, a collection of production rules that expand each symbol into some larger string of symbols, an initial "axiom" string from which to begin construction, and a mechanism for translating the generated strings into geometric structures. L-systems were introduced and developed in 1968 by Aristid Lindenmayer, a Hungarian theoretical biologist and botanist at the University of Utrecht. Lindenmayer used L-systems to describe the behaviour of plant cells and to model the growth processes of plant development. L-systems have also been used to model the morphology of a variety of organisms and can be used to generate self-similar fractals such as iterated function systems.

Origins

As a biologist, Lindenmayer worked with yeast and filamentous fungi and studied the growth patterns of various types of algae, such as the blue/green bacteria Anabaena catenula. Originally the L-systems were devised to provide a formal description of the development of such simple multicellular organisms, and to illustrate the neighbourhood relationships between plant cells. Later on, this system was extended to describe higher plants and complex branching structures.

Ülüş system

Ülüş system was the administrative system of the historical Turkic and Mongolic states. The noun Üleş in Turkish means "share" and the verb "üleş-mek" means to share.

The system

According to historian Halil İnalcık, the sovereignty didn't belong solely to the khagan (king) but it belonged to the members of the khagan's family. Thus the khagan allocated each member of the family a share of the country. This share was called ülüş. According to Kürşat Kocak however, ülüş practice included high level state officials also. This resembles the fief system in Medieval Europe. But Lev Gumilyov stresses that it was not a European type feudalism. According to Lev Gümiloy the system was developed in the Sothern Xiongnu during the second century AD. It was used by the Turkic Khaganate , Uighur Khaganette , Mongol Empire and the other political powers of the central Asia.

Example

In the Turkic Empire (551-744) during the reign of Taspar Khagan in 576, there were 8 üleşes. (see Göktürk family tree).

IBM 473L Command and Control System

The IBM 473L Command and Control System (473L System, 473L colloq.) was a USAFCold War "Big L" Support System with computer equipment at The Pentagon and, in Pennsylvania, the Alternate National Military Command Center nuclear bunker. Each 473L site included a Data Processing Subsystem (DPSS), Integrated Console Subsystem (ICSS), Large Panel Display Subsystem, and Data Communications Subsystem (Automatic Digital Network interface: "AUTODIN Data Terminal Bay"). The "System 473L" was an "on-line, real-time information processing system designed to facilitate effective management of USAF resources, particularly during emergency situations" e.g., for: "situation monitoring, resource monitoring, plan evaluation, plan generation and modification, and operations monitoring". In 1967, the 473L System was used during the "HIGH HEELS 67" exercise "to test the whole spectrum of command in a strategic crisis".

Background