vertical shaft impactor, a type of impact crusher vertical speed indicator , an instrument in an aircraft monitoring rate of descent or climb very short introductions , a series of books published by oxford university press
caving as a specialized pursuit was pioneered by édouard-alfred martel 1859–1938 , who first achieved the descent and exploration of the gouffre de padirac, in france, as early as 1889 and the first complete descent of a 110-metre wet vertical shaft at gaping gill in 1895. he developed his own techniques based on ropes and metallic ladders .
the spindle may be raised and lowered relative to the shaper's table, and rotates between 3,000 and 10,000 rpm, with stock running along a vertical fence. wood shaper cutter heads typically have three blades, and turn at 1/2 to 1/8th the speed of smaller, much less expensive two-bladed bits used on a hand-held wood router.
each explosive blast dislodges about 70,000 tons of granite, which is transported by dump truck to the primary crusher, which reduces it to lumps no bigger than nine inches in diameter. it is then transferred by conveyor belt to a heap that covers the 'glory hole', a 1,000 ft 300 m vertical shaft 10 ft 3 m in diameter, which is permanently full of rocks.
the yusufeli dam is an arch dam under construction on the çoruh river near yusufeli in artvin province within the eastern black sea region of turkey.the yusufeli dam will be the second largest dam within the larger çoruh river development plan, which plans to build 13 dams, of which two are operational and another two are under construction.
an aircraft is a vehicle that is able to fly by gaining support from the air.it counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.common examples of aircraft include airplanes, helicopters, airships including blimps , gliders, paramotors and hot air balloons.