Engineering and technology notes

Nikolai Vavilov

Jovan Stosic June 6, 2020

Nikolai Ivanovich Vavilov ForMemRS[3] HFRSE (Russian: Николай Иванович Вавилов, IPA: [nʲɪkɐˈlaj ɪˈvanəvʲɪtɕ vɐˈvʲiləf] 25 November [O.S. 13 November] 1887 – 26 January 1943) was a prominent Russian and Soviet agronomist, botanist and geneticist best known for having identified the centers of origin of cultivated plants. He devoted his life to the study and improvement of wheat, corn, and other cereal crops that sustain the global population.[4][5][6][7][8] Vavilov’s work was criticized by Trofim Lysenko, whose anti-Mendelian concepts of plant biology had won favor with Joseph Stalin. As a result, Vavilov was arrested and subsequently sentenced to death in July 1941. Although his sentence was commuted to twenty years’ imprisonment, he died in prison in 1943.

https://en.wikipedia.org/wiki/Nikolai_Vavilov

Crontab Day of the Week syntax

Jovan Stosic May 23, 2020

0 and 7 both stand for Sunday, you can use the one you want, so writing 0-6 or 1-7 has the same result.

Also, as suggested by @Henrik, it is possible to replace numbers by shortened name of days, such as MON, THU, etc:

0 - Sun      Sunday
1 - Mon      Monday
2 - Tue      Tuesday
3 - Wed      Wednesday
4 - Thu      Thursday
5 - Fri      Friday
6 - Sat      Saturday
7 - Sun      Sunday

Graphically:

 ┌────────── minute (0 - 59)
 │ ┌──────── hour (0 - 23)
 │ │ ┌────── day of month (1 - 31)
 │ │ │ ┌──── month (1 - 12)
 │ │ │ │ ┌── day of week (0 - 6 => Sunday - Saturday, or
 │ │ │ │ │                1 - 7 => Monday - Sunday)
 ↓ ↓ ↓ ↓ ↓
 * * * * * command to be executed

Finally, if you want to specify day by day, you can separate days with commas, for example SUN,MON,THU will exectute the command only on sundays, mondays on thursdays.

https://stackoverflow.com/questions/18919151/crontab-day-of-the-week-syntax