Decimal time
Decimal time is the representation of the time with decimal subdivisions.
history
China
There are around 50 different historical calendars in China . For most of China's three thousand year history, decimal time was used, often alongside duodecimal timekeeping. The day (from midnight to midnight) was initially divided into 100 units ( ke刻; pinyin : kè ). One ke corresponded to 14.4 minutes. During shorter periods of Chinese history, the day was also divided into 120, 96 or 108 Ke . Later a division of the day into two times 12 hours ( Shi ) was used and Ke was extended to a quarter of an hour.
The time unit Ke was divided into 100 or 60 Fen , depending on the calendar , which corresponded to around 9 or 15 seconds.
France
The French introduced decimal time as part of their revolutionary calendar and divided a day into 10 decimal hours. Each hour had 100 decimal minutes. Each decimal minute had 100 decimal seconds. The decree of November 24, 1793 (4 Frimaire II) read:
«XI. Le jour, de minuit à minuit, est divisé en dix parties ou heures, chaque partie en dix autres, ainsi de suite jusqu'à la plus petite portion commensurable de la durée. La centième partie de l'heure est appelée minute decimale ; The centième partie de la minute est appelée seconde décimale . »
"XI. The day, from midnight to midnight, is divided into ten parts or hours, each part into ten others, until the smallest measurable unit is reached. The hundredth of an hour should be called the decimal minute. The hundredth of a minute should be called a decimal second. "
So it should read "5 am noon" or "10 am midnight". Some clocks from that time showed both times, the decimal and the traditional. The decimal time was abolished as a generally valid unit of time in 1795.
Usage today
Decimal places of the Julian day
The most common today is the decimal time in the decimal places of the Julian date , a consecutive numbering of the days. However, the Julian date is not used to represent the time, but to calculate with time. The Julian date is then usually represented in binary form , compare hexadecimal time .
Compare also fraction of a day .
Swatch Internet Time
The Swiss company Swatch introduced the so-called Internet time in 1998 . This divides the day into 1000 .beats and should be valid worldwide . The start of the day is set at 12:00 a.m. CET , Biel Mean Time (BMT) named after the headquarters of the Swatch Group . This era could not prevail.
University of Munich
The Ludwig Maximilians University of Munich divides the day into tenths of an hour for time recording , with the time actually being printed in these units on stamp cards. It is therefore a variant of the industrial minute (0.1 instead of 0.01 hours) and not a decimal division of the day.
Deutsche Bahn
Internally , times are calculated and specified in tenths of a minute (one tenth of a minute = six seconds). The internal timetables are accurate to a tenth of a minute.
conversion
There are 86,400 sexagesimal seconds and 100,000 decimal seconds per day.
- A decimal second has 86,400 / 100,000 = 0.864 sexagesimal seconds.
- A decimal minute has 1440/1000 = 1.44 sexagesimal minutes.
- A decimal hour has 24/10 = 2.4 duodecimal hours.
Individual evidence
- ↑ LMU: time units on the stamp card .
- ↑ Martin Kopp: Hamburg's timetables: The S-Bahn mastermind thinks in tenths of a minute . In: THE WORLD . November 18, 2012 ( welt.de [accessed December 1, 2017]).
- ↑ Michael Evers: Rail transport: Train timetable makers also plan headwinds . In: THE WORLD . June 11, 2014 ( welt.de [accessed December 1, 2017]).