搜尋結果
Worldwide distribution of country calling codes. Regions are coloured by first digit. Country calling codes, country dial-in codes, international subscriber dialing (ISD) codes, or most commonly, telephone country codes are telephone number prefixes for reaching telephone subscribers in foreign countries or areas via international telecommunication networks.
Google is also the largest search engine, mapping and navigation application, email provider, office suite, online video platform, photo and cloud storage provider, mobile operating system, web browser, machine learning framework, and AI virtual assistant provider in the world as measured by market share. [18]
The Schengen Area (English: /ˈʃɛŋən/ SHENG-ən, Luxembourgish: [ˈʃæŋən] ⓘ) is an area encompassing 29 European countries that have officially abolished border controls at their mutual borders. Being an element within the wider area of freedom, security and justice policy of the European Union (EU), it mostly functions as a single ...
- Etymology
- Uses
- Mechanism
- History
- Rationale
- Future
- See Also
- External Links
The official abbreviation for Coordinated Universal Time is UTC. This abbreviation comes as a result of the International Telecommunication Union and the International Astronomical Union wanting to use the same abbreviation in all languages. The compromise that emerged was UTC,which conforms to the pattern for the abbreviations of the variants of U...
Time zones around the world are expressed using positive or negative offsets from UTC, as in the list of time zones by UTC offset. The westernmost time zone uses UTC−12, being twelve hours behind UTC; the easternmost time zone uses UTC+14, being fourteen hours ahead of UTC. In 1995, the island nation of Kiribati moved those of its atolls in the Lin...
UTC divides time into days, hours, minutes, and seconds. Days are conventionally identified using the Gregorian calendar, but Julian day numbers can also be used. Each day contains 24 hours and each hour contains 60 minutes. The number of seconds in a minute is usually 60, but with an occasional leap second, it may be 61 or 59 instead. Thus, in the...
In 1928, the term Universal Time (UT) was introduced by the International Astronomical Union to refer to GMT, with the day starting at midnight. Until the 1950s, broadcast time signalswere based on UT, and hence on the rotation of the Earth. In 1955, the caesium atomic clock was invented. This provided a form of timekeeping that was both more stabl...
Earth's rotational speed is very slowly decreasing because of tidal deceleration; this increases the length of the mean solar day. The length of the SI second was calibrated on the basis of the second of ephemeris time and can now be seen to have a relationship with the mean solar day observed between 1750 and 1892, analysed by Simon Newcomb. As a ...
As the Earth's rotation continues to slow, positive leap seconds will be required more frequently. The long-term rate of change of LOD is approximately +1.7 ms per century. At the end of the 21st century, LOD will be roughly 86,400.004 s, requiring leap seconds every 250 days. Over several centuries, the frequency of leap seconds will become proble...
CurrentUTC timeW3C Specification about UTC Date and Time and RFC 3339, based on ISO 8601Silicon Valley is a region in Northern California that is a global center for high technology and innovation. Located in the southern part of the San Francisco Bay Area, it corresponds roughly to the geographical area of the Santa Clara Valley. [1] [2] [3] The term "Silicon Valley" refers to the area in which high-tech business has proliferated ...
55.263 494 06. e2 ⋅ eV −1 ⋅ μm −1. Vacuum permittivity, commonly denoted ε0 (pronounced "epsilon nought" or "epsilon zero"), is the value of the absolute dielectric permittivity of classical vacuum. It may also be referred to as the permittivity of free space, the electric constant, or the distributed capacitance of the vacuum.
Various tribes of the Algonquian-speaking Piscataway people, also known as the Conoy, inhabited the lands around the Potomac River and present-day Washington, D.C., when Europeans first arrived and colonized the region in the early 17th century. The Nacotchtank, also called the Nacostines by Catholic missionaries, maintained settlements around the Anacostia River in present-day Washington, D.C ...
