Pay close attention to me, with 6 million difference friend plays together turn ~ of science and technology
Should produce immediately recently not quite not little thing.
Incident is similar the Y2k incident when 2000.
In the 20 centuries that the computer is come out by the invention, everybody thinks the question is simpler at the beginning, feel software won't be used very long, represent time with two digit word then.
Very apparent. . . In 19XX year when the thing that do not have what, but can appear 2000 problem: The computer is come up against " 00 " meeting understanding is 1900.
A lot of programs move may appear problem, equipment quits movement possibly even. . .
Take this problem seriously because of governmental industry height nevertheless, did not make a large-scale trouble finally so.
What the Unix system that present server uses generally uses is time of expression of integer of 32 binary systems, enough use to 2038 ～
The question that does not pass difference to judge gentleman to want this time to say is extremely urgent, GPS time service retroflexions problem.
Everybody should have listened to GPS, it is the satellitic series that American department of defense locates to give army and launchs, share 24 satellites to comprise, turn to whole world folk to use gradually later.
This covers a system besides fixed position, still having an effect is time service.
Global each district can correspond together, the job, a very main factor needs to maintain, it is hour.
Perhaps each district can be put in time difference, but what say here is the error that time passes.
Spent a hour one day likewise, cannot clock had shown 59 seconds here, you there crossed 01 seconds 24 hours 00 minutes.
Daily life differs a 9 seconds to concern not quite, but after time became long, bank system, airliner system, stock market open quotation can suffer very big effect etc.
Spoken parts in an opera, everybody's clock should keep consistent.
The reason that can create clock difference is very simple, present timing method still is measured substantially shake frequency, oscillation number is measured after for instance commonly used crystal clock gives crystal electric conduction namely- - every other writes down one second 8180 times 14.31 million.
Atomic Zhong Hui is a few more accurate, for example the frequency of cesium-beam atomic clock is oscillation writes down one second every 9192631770.
But each district can have other factor with different clock hard to avoid, for example voltaic influence, magnetic field influence, the person is an influence. . . Doing an accuracy to ask when you when extremely high issue, the thing with big fart is interference.
Perhaps say. . . Relativistic: You sat one day plane, be in the condition with mobile high speed, because this time has been met a few slower, curtilage I a day crossed 1 second in the home, but you may be 0.999912345 seconds.
Good. . . Since error hard avoid, that we no matter error, big housekeeping money is same a bell.
Perhaps say a bit more actually, the list that everybody takes him and same an origin calibration.
This is " time service " , our country has " country of the Chinese Academy of Sciences time service center " .
So the issue came, when local ball is apart from further two ground to want calibration time, what can you produce?
Assume we are put in China, so when American sends time service to request, meet such:
The limit that information passes rate is velocity of light, our collect whole calculate it 300 thousand kilometre / second.
The situation center be apart of China and United States 11657 kilometre.
11657 kilometre? 300000 kilometre / second of second = 0.039
Time service sends a request, feedback again time service, the flower has error of about 0.08 seconds in the time on the road, one day awards nowadays to come for many times, the error is quite considerable still. . .
So look, ground time service has a few limitation. . .
Is that in the sky?
The GPS time service that a moment ago mentioned can say here, GPS can take fixed position not only, OK also time service.
The atomic clock of high accuracy is contained on every GPS satellite, they back up each other and correct time, and control station communication issue an official calendar with the ground regularly.
The consideration transmits speed relative to speed and signal, GPS time service still can eliminate an error through a few formula, already accurate, to the whole world very fair.
The time computation of GPS is comprised by week and second, a week is equal to 604800 seconds, that is to say every time second number is recorded 604800 can clear, week count is met + 1 week.
But the likelihood is resource finite, the computation of the week in GPS used 10 binary digits to convey only, that is to say upper limit can plan 10 of 2 square- - 1024 weeks.
Of hole dad is. . . Local carry is done not have after week count became full, still meet as usual clears. . .
If receive the manufacturer of equipment of GPS time service to did not prepare ahead of schedule, before then the time of a not careful equipment rolls the likelihood 19 years.
Be in for example spaceflight, electric power, in the very sensitive to time domain such as finance, time mistake is catastrophic. . .
This time roll time place, it is Beijing time on April 7, 2019 in the morning 7 when 59 minutes of 42 seconds.
Leave so that exceed it seems that close ah. . .
Also do not have actually so terrible, a lot of methods go avoid, had happened 1999, what thing also is done not have.
Average means of settlement updates software namely, notice time service has roll, if having, the attention times begin time place to want to update.
In last few years the equipment of research and development can consider this issue commonly, it is good that if do not have some word couplet nets,scroll is updated.
Bother a little of a few embedded systematic criterion need and manufacturer connection, if did not shift to an earlier date,preparation has to make the best of time then. (although difference judges gentleman to believe the professional level with them, often noticed this issue early)
Plant of a few facility has reminded a client the attention is updated
Some news say in that day the plane cannot sit, but present plane relies on GPS data not completely actually, just do a position to consult, won't disturb flight safety. (this view comes from red star news of Chen Jianguo of senior to civil aviaton pilot interview)
If because this blemish bothers a person,you feel GPS is old very the word of accurate. . . Fight with north ah it is very mature now that the north of ～ our country fights a system, many domestic manufacturer had begun to turn north fights time service ～
Be in that day so, actually your what also need not work, do not want credulous what rumor, cross holiday of a tomb-sweeping day to go well ～
Reference material: Defend guide information " count of week of focusing Piao GPS retroflexions draw near, will look! " red star news " on April 6 by plane very dangerous? Senior pilot was responded to "Acknowledgment reads ~
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