A time standard is a specification for measuring time: either the rate at which time passes; or points in time; or both. In modern times, several time specifications have been officially recognized as standards, where formerly they were matters of custom and practice. An example of a kind of time standard can be a time scale, specifying a method for measuring divisions of time. A standard for civil time can specify both time intervals and time-of-day.
Standardized time measurements are made using a clock to count periods of some cyclic change, which may be either the changes of a natural phenomenon or of an artificial machine.
Historically, time standards were often based on the Earth's rotational period. From the late 17th century to the 19th century it was assumed that the Earth's daily rotational rate was constant. Astronomical observations of several kinds, including eclipse records, studied in the 19th century, raised suspicions that the rate at which Earth rotates is gradually slowing and also shows small-scale irregularities, and this was confirmed in the early twentieth century. Time standards based on Earth rotation were replaced (or initially supplemented) for astronomical use from 1952 onwards by an ephemeris time standard based on the Earth's orbital period and in practice on the motion of the Moon. 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.
Kathleen Alice "Kathy" Mattea (pronounced ma-TAY-a) (born June 21, 1958, in South Charleston, West Virginia) is an American country music and bluegrass performer who often brings folk, Celtic and traditional country sounds to her music. Active since 1983 as a recording artist, she has recorded seventeen albums and has charted more than thirty singles on the Billboard Hot Country Singles & Tracks charts. This total includes the number one hits "Goin' Gone", "Eighteen Wheels and a Dozen Roses", "Come From the Heart" and "Burnin' Old Memories", as well as twelve additional Top Ten singles.
Mattea was born in South Charleston, West Virginia, because it had the nearest hospital to her parents' home in Cross Lanes, where she grew up, graduating from nearby Nitro High School. She discovered her love of singing at Girl Scout camp. In 1976, while attending West Virginia University, she joined the bluegrass band Pennsboro, and two years later dropped out of school to move to Nashville. She worked as a tour guide at the Country Music Hall of Fame, did backup vocal work for Bobby Goldsboro, and sang demos for several Nashville songwriters and publishers including Nashville songwriter/producer Byron Hill who brought her to the attention of Frank Jones (then head of Mercury Records), who signed her to her first record deal in 1983.
Amrullah Saleh (Persian: امرالله صالح; born 1971) is an Afghan politician who last served as head of the Afghan National Directorate of Security. In 1997, at the age of 24, he was appointed by anti-Taliban leader Ahmad Shah Massoud to lead the United Front's (Northern Alliance) liaison office inside the Afghan Embassy in Dushanbe handling contacts to international non-governmental (humanitarian) organizations and intelligence agencies. After the fall of the Taliban regime, Saleh was appointed by President Hamid Karzai in early 2004 to lead the National Directorate of Security. Due to political differences with Karzai, Saleh resigned his position in 2010. He is currently leading one of the strongest Afghan pro-democracy and anti-Taliban movements, the Basej-i Milli (National Movement) or Afghanistan Green Trend, with about 10,000 of his supporters rallying against the Taliban in Kabul in 2011.
Amrullah Saleh was born in the Panjshir Province of Afghanistan in 1971.
In the late 1990s, in his early 20s, Saleh worked for the anti-Taliban resistance, the United Front (Northern Alliance), under Ahmad Shah Massoud. In 1997, Saleh was appointed to lead Massoud's international liaison office in Dushanbe, Tajikistan, where he served as a coordinator for non-governmental (humanitarian) organizations and as a liaision partner for foreign intelligence agencies.
Mohammad Umer Daudzai (Pashto: محمد عمر داودزی - born October 12, 1957), is the Chief of Staff of Afghan President Hamid Karzai from 2003 to 2005 and then from 2007 to present. He is a former member of the Hezbi Islami and was from 2005 until 2007 Afghan's Ambassador in Iran.
Mohammad Omar Daudzai was born on October 12, 1957 in the Qarabagh District of the Kabul Province in Afghanistan. He grew up and completed his primary education in his home district of Qarabagh. In order to continue his higher education, Omar moved to the capital city Kabul.
During the 1980s Daudzai became active in the resistance against the Sovjet-occupation and joined the Mujahideen group of Gulbuddin Hekmatyar: Hezbi Islami. Also during the Civil War he kept fighting with the Pakistan backed Hezbi Islami to take over the country.
During the Taliban era Daudzai decided to settle in Peshawar, Pakistan, and began working for the organization Save the Children. While working there through a scholarship program, he was able to go to the Oxford University in the United Kingdom for his Masters in Science. After completing his Masters he came back to work for the Swedish Committee in Jalalabad, Afghanistan. In 1996 he moved to Islamabad, Pakistan, where he started working for the United Nations Development Program (UNDP). In 2001 he moved to Geneva, Switzerland, where he assumed the role of "Area Development Specialist" in UNDP Geneva.