Bordeaux is a port city on the Garonne in the Gironde department in Southwestern France. The municipality of Bordeaux proper has a population of 252,040. Together with its suburbs and satellite towns, Bordeaux is the centre of the Bordeaux Métropole. With 1,195,335 in the metropolitan area, it is the sixth-largest in France, after Paris, Lyon and Lille, it is the capital of the Nouvelle-Aquitaine region, as well as the prefecture of the Gironde department. Its inhabitants are called "Bordelais" or "Bordelaises"; the term "Bordelais" may refer to the city and its surrounding region. Being at the center of a major wine-growing and wine-producing region, Bordeaux remains a prominent powerhouse and exercises significant influence on the world wine industry although no wine production is conducted within the city limits, it is home to the world's main wine fair and the wine economy in the metro area takes in 14.5 billion euros each year. Bordeaux wine has been produced in the region since the 8th century.
The historic part of the city is on the UNESCO World Heritage List as "an outstanding urban and architectural ensemble" of the 18th century. After Paris, Bordeaux has the highest number of preserved historical buildings of any city in France. In historical times, around 567 BC it was the settlement of a Celtic tribe, the Bituriges Vivisci, who named the town Burdigala of Aquitanian origin; the name Bourde is still the name of a river south of the city. In 107 BC, the Battle of Burdigala was fought by the Romans who were defending the Allobroges, a Gallic tribe allied to Rome, the Tigurini led by Divico; the Romans were defeated and their commander, the consul Lucius Cassius Longinus, was killed in the action. The city fell under Roman rule around its importance lying in the commerce of tin and lead, it became capital of Roman Aquitaine, flourishing during the Severan dynasty. In 276 it was sacked by the Vandals. Further ravage was brought by the same Vandals in 409, the Visigoths in 414, the Franks in 498, beginning a period of obscurity for the city.
In the late 6th century, the city re-emerged as the seat of a county and an archdiocese within the Merovingian kingdom of the Franks, but royal Frankish power was never strong. The city started to play a regional role as a major urban center on the fringes of the newly founded Frankish Duchy of Vasconia. Around 585, Gallactorius is fighting the Basque people; the city was plundered by the troops of Abd er Rahman in 732 after they stormed the fortified city and overwhelmed the Aquitanian garrison. Duke Eudes mustered a force ready to engage the Umayyads outside Bordeaux taking them on in the Battle of the River Garonne somewhere near the river Dordogne; the battle had a high death toll. Although Eudes was defeated here, he saved part of his troops and kept his grip on Aquitaine after the Battle of Poitiers. In 735, the Aquitanian duke Hunald led a rebellion after his father Eudes's death, at which Charles responded by sending an expedition that captured and plundered Bordeaux again, but did not retain it for long.
The following year, the Frankish commander descended again to Aquitaine, but clashed in battle with the Aquitanians and left to take on hostile Burgundian authorities and magnates. In 745, Aquitaine faced yet another expedition by Charles's sons Pepin and Carloman, against Hunald, the Aquitanian princeps strong in Bordeaux. Hunald was defeated, his son Waifer replaced him, confirmed Bordeaux as the capital city. During the last stage of the war against Aquitaine, it was one of Waifer's last important strongholds to fall to King Pepin the Short's troops. Next to Bordeaux, Charlemagne built the fortress of Fronsac on a hill across the border with the Basques, where Basque commanders came over to vow loyalty to him. In 778, Seguin was appointed count of Bordeaux undermining the power of the Duke Lupo, leading to the Battle of Roncevaux Pass that year. In 814, Seguin was made Duke of Vasconia, but he was deposed in 816 for failing to suppress or sympathise with a Basque rebellion. Under the Carolingians, sometimes the Counts of Bordeaux held the title concomitantly with that of Duke of Vasconia.
They were meant to keep the Basques in check and defend the mouth of the Garonne from the Vikings when the latter appeared c. 844 in the region of Bordeaux. In Autumn 845, count Seguin II marched on the Vikings, who were assaulting Bordeaux and Saintes, but he was captured and executed. No bishops were mentioned during part of the 9th in Bordeaux. From the 12th to the 15th century, Bordeaux regained importance following the marriage of Duchess Eléonore of Aquitaine with the French-speaking Count Henri Plantagenet, born in Le Mans, who became, within months of their wedding, King Henry II of England; the city flourished due to the wine trade, the cathedral of St. André was built, it was the capital of an independent state under Edward, the Black Prince, but in the end, after the Battle of Castillon, it was annexed by France which extended its territory. The Château Trompette and the Fort du Hâ, built by Charles VII of France, were the symbols of the new domination, which however deprived the city of its wealth by halting the wine commerce with England.
In 1462, Bordeaux obtained a parliament, but regained importance only in the 16th century when it became the centre of the distribution of sugar and slaves from the West Indies along with the traditional wine. Bordeaux adhered to the Fronde
Meteorology is a branch of the atmospheric sciences which includes atmospheric chemistry and atmospheric physics, with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not occur until the 18th century; the 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data, it was not until after the elucidation of the laws of physics and more the development of the computer, allowing for the automated solution of a great many equations that model the weather, in the latter half of the 20th century that significant breakthroughs in weather forecasting were achieved. An important domain of weather forecasting is marine weather forecasting as it relates to maritime and coastal safety, in which weather effects include atmospheric interactions with large bodies of water. Meteorological phenomena are observable weather events that are explained by the science of meteorology.
Meteorological phenomena are described and quantified by the variables of Earth's atmosphere: temperature, air pressure, water vapour, mass flow, the variations and interactions of those variables, how they change over time. Different spatial scales are used to describe and predict weather on local and global levels. Meteorology, atmospheric physics, atmospheric chemistry are sub-disciplines of the atmospheric sciences. Meteorology and hydrology compose the interdisciplinary field of hydrometeorology; the interactions between Earth's atmosphere and its oceans are part of a coupled ocean-atmosphere system. Meteorology has application in many diverse fields such as the military, energy production, transport and construction; the word meteorology is from the Ancient Greek μετέωρος metéōros and -λογία -logia, meaning "the study of things high in the air". The ability to predict rains and floods based on annual cycles was evidently used by humans at least from the time of agricultural settlement if not earlier.
Early approaches to predicting weather were practiced by priests. Cuneiform inscriptions on Babylonian tablets included associations between rain; the Chaldeans differentiated 46 ° halos. Ancient Indian Upanishads contain mentions of seasons; the Samaveda mentions sacrifices to be performed. Varāhamihira's classical work Brihatsamhita, written about 500 AD, provides evidence of weather observation. In 350 BC, Aristotle wrote Meteorology. Aristotle is considered the founder of meteorology. One of the most impressive achievements described in the Meteorology is the description of what is now known as the hydrologic cycle; the book De Mundo noted If the flashing body is set on fire and rushes violently to the Earth it is called a thunderbolt. They are all called ` swooping bolts'. Lightning is sometimes smoky, is called'smoldering lightning". At other times, it travels in crooked lines, is called forked lightning; when it swoops down upon some object it is called'swooping lightning'. The Greek scientist Theophrastus compiled a book on weather forecasting, called the Book of Signs.
The work of Theophrastus remained a dominant influence in the study of weather and in weather forecasting for nearly 2,000 years. In 25 AD, Pomponius Mela, a geographer for the Roman Empire, formalized the climatic zone system. According to Toufic Fahd, around the 9th century, Al-Dinawari wrote the Kitab al-Nabat, in which he deals with the application of meteorology to agriculture during the Muslim Agricultural Revolution, he describes the meteorological character of the sky, the planets and constellations, the sun and moon, the lunar phases indicating seasons and rain, the anwa, atmospheric phenomena such as winds, lightning, floods, rivers, lakes. Early attempts at predicting weather were related to prophecy and divining, were sometimes based on astrological ideas. Admiral FitzRoy tried to separate scientific approaches from prophetic ones. Ptolemy wrote on the atmospheric refraction of light in the context of astronomical observations. In 1021, Alhazen showed that atmospheric refraction is responsible for twilight.
St. Albert the Great was the first to propose that each drop of falling rain had the form of a small sphere, that this form meant that the rainbow was produced by light interacting with each raindrop. Roger Bacon was the first to calculate the angular size of the rainbow, he stated. In the late 13th century and early 14th century, Kamāl al-Dīn al-Fārisī and Theodoric of Freiberg were the first to give the correct explanations for the primary rainbow phenomenon. Theoderic went further and explained the secondary rainbow. In 1716, Edmund Halley suggested that aurorae are caused by "magnetic effluvia" moving along the Earth's magnetic field lines. In 1441, King Sejong's son, Prince Munjong of Korea, invented the first standardized rain gauge; these were sent throughout the Joseon dynasty of Korea as an official tool to assess land taxes based
Wolf–Rayet stars abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectra showing prominent broad emission lines of ionised helium and ionised nitrogen or carbon. The spectra indicate high surface enhancement of heavy elements, depletion of hydrogen, strong stellar winds, their surface temperatures range from 30,000 K to around 200,000 K, hotter than all other stars. Classic Wolf–Rayet stars are evolved, massive stars that have lost their outer hydrogen and are fusing helium or heavier elements in the core. A subset of the population I WR stars show hydrogen lines in their spectra and are known as WNh stars. A separate group of stars with WR spectra are the central stars of planetary nebulae, post asymptotic giant branch stars that were similar to the Sun while on the main sequence, but have now ceased fusion and shed their atmospheres to reveal a bare carbon-oxygen core. All Wolf–Rayet stars are luminous objects due to their high temperatures—thousands of times the bolometric luminosity of the Sun for the CSPNe, hundreds of thousands L☉ for the Population I WR stars, to over a million L☉ for the WNh stars—although not exceptionally bright visually since most of their radiation output is in the ultraviolet.
The naked-eye stars Gamma Velorum and Theta Muscae, as well as the most massive known star, R136a1 in 30 Doradus, are all Wolf–Rayet stars. In 1867, using the 40 cm Foucault telescope at the Paris Observatory, astronomers Charles Wolf and Georges Rayet discovered three stars in the constellation Cygnus that displayed broad emission bands on an otherwise continuous spectrum. Most stars only display absorption lines or bands in their spectra, as a result of overlying elements absorbing light energy at specific frequencies, so these were unusual objects; the nature of the emission bands in the spectra of a Wolf–Rayet star remained a mystery for several decades. Edward C. Pickering theorized that the lines were caused by an unusual state of hydrogen, it was found that this "Pickering series" of lines followed a pattern similar to the Balmer series, when half-integer quantum numbers were substituted, it was shown that the lines resulted from the presence of helium. Pickering noted similarities between Wolf–Rayet spectra and nebular spectra, this similarity led to the conclusion that some or all Wolf Rayet stars were the central stars of planetary nebulae.
By 1929, the width of the emission bands was being attributed to Doppler broadening, hence that the gas surrounding these stars must be moving with velocities of 300–2400 km/s along the line of sight. The conclusion was that a Wolf–Rayet star is continually ejecting gas into space, producing an expanding envelope of nebulous gas; the force ejecting the gas at the high velocities observed is radiation pressure. It was well known that many stars with Wolf Rayet type spectra were the central stars of planetary nebulae, but that many were not associated with an obvious planetary nebula or any visible nebulosity at all. In addition to helium, emission lines of carbon and nitrogen were identified in the spectra of Wolf–Rayet stars. In 1938, the International Astronomical Union classified the spectra of Wolf–Rayet stars into types WN and WC, depending on whether the spectrum was dominated by lines of nitrogen or carbon-oxygen respectively. In 1969, several CSPNe with strong OVI emissions lines were grouped under a new "OVI sequence", or just OVI type.
These were subsequently referred to as stars. Similar stars not associated with planetary nebulae were described shortly after and the WO classification was also adopted for population I WR stars; the understanding that certain late, sometimes not-so-late, WN stars with hydrogen lines in their spectra are at a different stage of evolution from hydrogen-free WR stars has led to the introduction of the term WNh to distinguish these stars from other WN stars. They were referred to as WNL stars, although there are late-type WN stars without hydrogen as well as WR stars with hydrogen as early as WN5. Wolf–Rayet stars were named on the basis of the strong broad emission lines in their spectra, identified with helium, carbon and oxygen, but with hydrogen lines weak or absent; the first system of classification split these into stars with dominant lines of ionised nitrogen and those with dominant lines of ionised carbon and sometimes oxygen, referred to as WN and WC respectively. The two classes WN and WC were further split into temperature sequences WN5-WN8 and WC6-WC8 based on the relative strengths of the 541.1nm HeII and 587.5 nm HeI lines.
Wolf–Rayet emission lines have a broadened absorption wing suggesting circumstellar material. A WO sequence has been separated from the WC sequence for hotter stars where emission of ionised oxygen dominates that of ionised carbon, although the actual proportions of those elements in the stars are to be comparable. WC and WO spectra are formally distinguished based on the absence of CIII emission. WC spectra generally lack the OVI lines that are strong in WO spectra; the WN spectral sequence was expanded to include WN2 - WN9, the definitions refined based on the relative strengths of the NIII lines at 463.4-464.1 nm and 531.4 nm, the NIV lines at 347.9-348.4 nm and 405.8 nm, the NV lines at 460.3 nm, 461.9 nm, 493.3-4
Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics and chemistry in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, stars, nebulae and comets. More all phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject is physical cosmology, the study of the Universe as a whole. Astronomy is one of the oldest of the natural sciences; the early civilizations in recorded history, such as the Babylonians, Indians, Nubians, Chinese and many ancient indigenous peoples of the Americas, performed methodical observations of the night sky. Astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, the making of calendars, but professional astronomy is now considered to be synonymous with astrophysics. Professional astronomy is split into theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects, analyzed using basic principles of physics.
Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. The two fields complement each other, with theoretical astronomy seeking to explain observational results and observations being used to confirm theoretical results. Astronomy is one of the few sciences in which amateurs still play an active role in the discovery and observation of transient events. Amateur astronomers have made and contributed to many important astronomical discoveries, such as finding new comets. Astronomy means "law of the stars". Astronomy should not be confused with astrology, the belief system which claims that human affairs are correlated with the positions of celestial objects. Although the two fields share a common origin, they are now distinct. Both of the terms "astronomy" and "astrophysics" may be used to refer to the same subject. Based on strict dictionary definitions, "astronomy" refers to "the study of objects and matter outside the Earth's atmosphere and of their physical and chemical properties," while "astrophysics" refers to the branch of astronomy dealing with "the behavior, physical properties, dynamic processes of celestial objects and phenomena."
In some cases, as in the introduction of the introductory textbook The Physical Universe by Frank Shu, "astronomy" may be used to describe the qualitative study of the subject, whereas "astrophysics" is used to describe the physics-oriented version of the subject. However, since most modern astronomical research deals with subjects related to physics, modern astronomy could be called astrophysics; some fields, such as astrometry, are purely astronomy rather than astrophysics. Various departments in which scientists carry out research on this subject may use "astronomy" and "astrophysics" depending on whether the department is affiliated with a physics department, many professional astronomers have physics rather than astronomy degrees; some titles of the leading scientific journals in this field include The Astronomical Journal, The Astrophysical Journal, Astronomy and Astrophysics. In early historic times, astronomy only consisted of the observation and predictions of the motions of objects visible to the naked eye.
In some locations, early cultures assembled massive artifacts that had some astronomical purpose. In addition to their ceremonial uses, these observatories could be employed to determine the seasons, an important factor in knowing when to plant crops and in understanding the length of the year. Before tools such as the telescope were invented, early study of the stars was conducted using the naked eye; as civilizations developed, most notably in Mesopotamia, Persia, China and Central America, astronomical observatories were assembled and ideas on the nature of the Universe began to develop. Most early astronomy consisted of mapping the positions of the stars and planets, a science now referred to as astrometry. From these observations, early ideas about the motions of the planets were formed, the nature of the Sun and the Earth in the Universe were explored philosophically; the Earth was believed to be the center of the Universe with the Sun, the Moon and the stars rotating around it. This is known as the geocentric model of the Ptolemaic system, named after Ptolemy.
A important early development was the beginning of mathematical and scientific astronomy, which began among the Babylonians, who laid the foundations for the astronomical traditions that developed in many other civilizations. The Babylonians discovered. Following the Babylonians, significant advances in astronomy were made in ancient Greece and the Hellenistic world. Greek astronomy is characterized from the start by seeking a rational, physical explanation for celestial phenomena. In the 3rd century BC, Aristarchus of Samos estimated the size and distance of the Moon and Sun, he proposed a model of the Solar System where the Earth and planets rotated around the Sun, now called the heliocentric model. In the 2nd century BC, Hipparchus discovered precession, calculated the size and distance of the Moon and inven
Virtual International Authority File
The Virtual International Authority File is an international authority file. It is a joint project of several national libraries and operated by the Online Computer Library Center. Discussion about having a common international authority started in the late 1990s. After a series of failed attempts to come up with a unique common authority file, the new idea was to link existing national authorities; this would present all the benefits of a common file without requiring a large investment of time and expense in the process. The project was initiated by the US Library of Congress, the German National Library and the OCLC on August 6, 2003; the Bibliothèque nationale de France joined the project on October 5, 2007. The project transitioned to being a service of the OCLC on April 4, 2012; the aim is to link the national authority files to a single virtual authority file. In this file, identical records from the different data sets are linked together. A VIAF record receives a standard data number, contains the primary "see" and "see also" records from the original records, refers to the original authority records.
The data are available for research and data exchange and sharing. Reciprocal updating uses the Open Archives Initiative Protocol for Metadata Harvesting protocol; the file numbers are being added to Wikipedia biographical articles and are incorporated into Wikidata. VIAF's clustering algorithm is run every month; as more data are added from participating libraries, clusters of authority records may coalesce or split, leading to some fluctuation in the VIAF identifier of certain authority records. Authority control Faceted Application of Subject Terminology Integrated Authority File International Standard Authority Data Number International Standard Name Identifier Wikipedia's authority control template for articles Official website VIAF at OCLC
Integrated Authority File
The Integrated Authority File or GND is an international authority file for the organisation of personal names, subject headings and corporate bodies from catalogues. It is used for documentation in libraries and also by archives and museums; the GND is managed by the German National Library in cooperation with various regional library networks in German-speaking Europe and other partners. The GND falls under the Creative Commons Zero licence; the GND specification provides a hierarchy of high-level entities and sub-classes, useful in library classification, an approach to unambiguous identification of single elements. It comprises an ontology intended for knowledge representation in the semantic web, available in the RDF format; the Integrated Authority File became operational in April 2012 and integrates the content of the following authority files, which have since been discontinued: Name Authority File Corporate Bodies Authority File Subject Headings Authority File Uniform Title File of the Deutsches Musikarchiv At the time of its introduction on 5 April 2012, the GND held 9,493,860 files, including 2,650,000 personalised names.
There are seven main types of GND entities: LIBRIS Virtual International Authority File Information pages about the GND from the German National Library Search via OGND Bereitstellung des ersten GND-Grundbestandes DNB, 19 April 2012 From Authority Control to Linked Authority Data Presentation given by Reinhold Heuvelmann to the ALA MARC Formats Interest Group, June 2012