drilling liner
41Trenchless technology — Trenchless technology, as the name implies, stands for subsurface construction works where less trenches or no continuous trenches are required to be dug. It is a rapidly growing sector of the construction and civil engineering industry. It can… …
42Diving support vessel — DSV Skandi Achiever in Aberdeen A diving support vessel is a ship that is used as a floating base for professional diving projects.[1] Commercial Diving Support Vessels emerged during the 1960s and 1970s when the need arose for …
43Research vessel — A research vessel (RV or R/V) is a ship designed and equipped to carry out research at sea. Research vessels carry out a number of roles. Some of these roles can be combined into a single vessel, others require a dedicated vessel. Due to the… …
44United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …
45Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
46Manapouri Hydroelectric Power Station — Manapouri Power Station The Manapouri Power Station machine hall …
47Earthquake — For other uses, see Earthquake (disambiguation). Global earthquake epicenters, 1963–1998 …
48Second Avenue Subway — Planned route of the NYC Subway Second Avenue Line ( T , in teal). Overview Type Rapid transit System …
49Montmorillonite — A sample of montmorillonite (unknown scale) General Category smectite, phyllosilicate …
50Uranium mining — The Ranger Uranium Mine in Australia …
