Practice
In the 21st century the cable jetting technique is used worldwide, from small optical telecom cables (1.8 mm diameter) in small microducts (3 mm internal diameter) up to large copper telecom cables (35 mm diameter) in large ducts (50 mm internal diameter). Jetting is done with a pressure of the compressed air in the order of 10 bar. With the jetting technique distances per blow of 3.5 km have been reached, while spliceless links of 12 km have been reached by placing jetting equipment in tandem. It is possible to install 12 km in one day with one small crew.
In mid 1990s the technique was also developed to install multiple smaller microducts, bundles, into a larger duct in one installation. This is called multi-ducting, microduct cabling, or bundle blowing. Each can hold a cable.
Another capability is to install a single cable or a bundle of small ducts into an occupied duct. The most cost driving activity of installing a network is the need for civil works. Thus, re-using ducts occupied with one cable, leaving some space, is a tempting and often possible and cost effective alternative.
Read more about this topic: Cable Jetting
Famous quotes containing the word practice:
“The practice of S/M is the creation of pleasure.... And that’s why S/M is really a subculture. It’s a process of invention. S/M is the use of a strategic relationship as a source of pleasure.”
—Michel Foucault (1926–1984)
“In a sense that I am unable to explicate further, the proponents of competing paradigms practice their trades in different worlds.”
—Thomas S. Kuhn (1922)
“As an example of just how useless these philosophers are for any practice in life there is Socrates himself, the one and only wise man, according to the Delphic Oracle. Whenever he tried to do anything in public he had to break off amid general laughter. While he was philosophizing about clouds and ideas, measuring a flea’s foot and marveling at a midge’s humming, he learned nothing about the affairs of ordinary life.”
—Desiderius Erasmus (c. 1466–1536)