caesium atomic clock造句

• Japan Standard Time is set by a caesium atomic clock in Tokyo.
• In 1955, the caesium atomic clock was invented.
• In 1967, the SI second was redefined in terms of the frequency supplied by a caesium atomic clock.
• This information is sent to the transmitter stations and is used to set a caesium atomic clock at each station.
• Caesium atomic clocks became operational in 1955, and quickly confirmed the evidence that the rotation of the earth fluctuated randomly.
• Caesium atomic clocks became operational in 1955, and their use provided further confirmation that the rotation of the earth fluctuated randomly.
• After the caesium atomic clock was invented, such clocks were used increasingly from the late 1950s as secondary realizations of ephemeris time ( ET ).
• The unit of TT is the SI second, the definition of which is currently based on the caesium atomic clock, but TT is not itself defined by atomic clocks.
• In 1968, Louis Essen, the inventor of the caesium atomic clock, and G . M . R . Winkler both independently proposed that steps should be of 1 s only.
• Caesium atomic clocks are extraordinarily accurate; if a clock had been made at the time of the dinosaurs, it would be off by less than four seconds ( after 80 million years ).
• The invention in 1955 of the caesium atomic clock has led to the replacement of older and purely astronomical time standards, for most practical purposes, by newer time standards based wholly or partly on atomic time.