Plasma is one of the four fundamental states of matter, was first described by chemist Irving Langmuir in the 1920s. Plasma can be artificially generated by heating or subjecting a neutral gas to a strong electromagnetic field to the point where an ionized gaseous substance becomes electrically conductive, long-range electromagnetic fields dominate the behaviour of the matter. Plasma and ionized gases have properties and display behaviours unlike those of the other states, the transition between them is a matter of nomenclature and subject to interpretation. Based on the surrounding environmental temperature and density ionized or ionized forms of plasma may be produced. Neon signs and lightning are examples of ionized plasma; the Earth's ionosphere is a plasma and the magnetosphere contains plasma in the Earth's surrounding space environment. The interior of the Sun is an example of ionized plasma, along with the solar corona and stars. Positive charges in ions are achieved by stripping away electrons orbiting the atomic nuclei, where the total number of electrons removed is related to either increasing temperature or the local density of other ionized matter.
This can be accompanied by the dissociation of molecular bonds, though this process is distinctly different from chemical processes of ion interactions in liquids or the behaviour of shared ions in metals. The response of plasma to electromagnetic fields is used in many modern technological devices, such as plasma televisions or plasma etching. Plasma may be the most abundant form of ordinary matter in the universe, although this hypothesis is tentative based on the existence and unknown properties of dark matter. Plasma is associated with stars, extending to the rarefied intracluster medium and the intergalactic regions; the word plasma comes from Ancient Greek πλάσμα, meaning'moldable substance' or'jelly', describes the behaviour of the ionized atomic nuclei and the electrons within the surrounding region of the plasma. Each of these nuclei are suspended in a movable sea of electrons. Plasma was first identified in a Crookes tube, so described by Sir William Crookes in 1879; the nature of this "cathode ray" matter was subsequently identified by British physicist Sir J.
J. Thomson in 1897; the term "plasma" was coined by Irving Langmuir in 1928. Lewi Tonks and Harold Mott-Smith, both of whom worked with Irving Langmuir in the 1920s, recall that Langmuir first used the word "plasma" in analogy with blood. Mott-Smith recalls, in particular, that the transport of electrons from thermionic filaments reminded Langmuir of "the way blood plasma carries red and white corpuscles and germs."Langmuir described the plasma he observed as follows: "Except near the electrodes, where there are sheaths containing few electrons, the ionized gas contains ions and electrons in about equal numbers so that the resultant space charge is small. We shall use the name plasma to describe this region containing balanced charges of ions and electrons." Plasma is a state of matter in which an ionized gaseous substance becomes electrically conductive to the point that long-range electric and magnetic fields dominate the behaviour of the matter. The plasma state can be contrasted with the other states: solid and gas.
Plasma is an electrically neutral medium of unbound negative particles. Although these particles are unbound, they are not "free" in the sense of not experiencing forces. Moving charged particles generate an electric current within a magnetic field, any movement of a charged plasma particle affects and is affected by the fields created by the other charges. In turn this governs collective behaviour with many degrees of variation. Three factors define a plasma: The plasma approximation: The plasma approximation applies when the plasma parameter, Λ, representing the number of charge carriers within a sphere surrounding a given charged particle, is sufficiently high as to shield the electrostatic influence of the particle outside of the sphere. Bulk interactions: The Debye screening length is short compared to the physical size of the plasma; this criterion means that interactions in the bulk of the plasma are more important than those at its edges, where boundary effects may take place. When this criterion is satisfied, the plasma is quasineutral.
Plasma frequency: The electron plasma frequency is large compared to the electron-neutral collision frequency. When this condition is valid, electrostatic interactions dominate over the processes of ordinary gas kinetics. Plasma temperature is measured in kelvin or electronvolts and is, informally, a measure of the thermal kinetic energy per particle. High temperatures are needed to sustain ionisation, a defining feature of a plasma; the degree of plasma ionisation is determined by the electron temperature relative to the ionization energy, in a relationship called the Saha equation. At low temperatures and electrons tend to recombine into bound states—atoms—and the plasma will become a gas. In most cases the electrons are close enough to thermal equilibrium that their temperature is well-defined; because of the large difference in ma
Postgraduate education, or graduate education in North America, involves learning and studying for academic or professional degrees, academic or professional certificates, academic or professional diplomas, or other qualifications for which a first or bachelor's degree is required, it is considered to be part of higher education. In North America, this level is referred to as graduate school; the organization and structure of postgraduate education varies in different countries, as well as in different institutions within countries. This article outlines the basic types of courses and of teaching and examination methods, with some explanation of their history. There are two main types of degrees studied for at the postgraduate level: academic and vocational degrees; the term degree in this context means the moving from one stage or level to another, first appeared in the 13th century. Although systems of higher education date back to ancient Greece, ancient Rome, ancient India and Arabian Peninsula, the concept of postgraduate education depends upon the system of awarding degrees at different levels of study, can be traced to the workings of European medieval universities Italians.
University studies took six years for a bachelor's degree and up to twelve additional years for a master's degree or doctorate. The first six years taught the faculty of the arts, the study of the seven liberal arts: arithmetic, astronomy, music theory, grammar and rhetoric; the main emphasis was on logic. Once a Bachelor of Arts degree had been obtained, the student could choose one of three faculties—law, medicine, or theology—in which to pursue master's or doctor's degrees; the degrees of master and doctor were for some time equivalent, "the former being more in favour at Paris and the universities modeled after it, the latter at Bologna and its derivative universities. At Oxford and Cambridge a distinction came to be drawn between the Faculties of Law and Theology and the Faculty of Arts in this respect, the title of Doctor being used for the former, that of Master for the latter." Because theology was thought to be the highest of the subjects, the doctorate came to be thought of as higher than the master's.
The main significance of the higher, postgraduate degrees was that they licensed the holder to teach. In most countries, the hierarchy of postgraduate degrees is: Master's degrees; these are sometimes placed in a further hierarchy, starting with degrees such as the Master of Arts and Master of Science degrees the Master of Philosophy degree, the Master of Letters degree. In the UK, master's degrees may be taught or by research: taught master's degrees include the Master of Science and Master of Arts degrees which last one year and are worth 180 CATS credits, whereas the master's degrees by research include the Master of Research degree which lasts one year and is worth 180 CATS or 90 ECTS credits and the Master of Philosophy degree which lasts two years. In Scottish Universities, the Master of Philosophy degree tends to be by research or higher master's degree and the Master of Letters degree tends to be the taught or lower master's degree. In many fields such as clinical social work, or library science in North America, a master's is the terminal degree.
Professional degrees such as the Master of Architecture degree can last to three and a half years to satisfy professional requirements to be an architect. Professional degrees such as the Master of Business Administration degree can last up to two years to satisfy the requirement to become a knowledgeable business leader. Doctorates; these are further divided into academic and professional doctorates. An academic doctorate can be awarded as a Doctor of Philosophy degree or as a Doctor of Science degree; the Doctor of Science degree can be awarded in specific fields, such as a Doctor of Science in Mathematics degree, a Doctor of Agricultural Science degree, a Doctor of Business Administration degree, etc. In some parts of Europe, doctorates are divided into the Doctor of Philosophy degree or "junior doctorate", the "higher doctorates" such as the Doctor of Science degree, awarded to distinguished professors. A doctorate is the terminal degree in most fields. In the United States, there is little distinction between a Doctor of Philosophy degree and a Doctor of Science degree.
In the UK, Doctor of Philosophy degrees are equivalent to 540 CATS credits or 270 ECTS European credits, but this is not always the case as the credit structure of doctoral degrees is not defined. In some countries such as Finland and Sweden, there is the degree of Licentiate, more advanced than a master's degree but less so than a Doctorate. Credits required are about half of those required for a doctoral degree. Coursework requirements are the same as for a doctorate, but the extent of original research required is not as high as for doctorate. Medical doctors for example ar
University of Portsmouth
The University of Portsmouth is a public university in the city of Portsmouth, England. The history of the university dates back to 1908, when the Park building opened as a Municipal college and public library, it was known as Portsmouth Polytechnic until 1992, when it was granted university status through the Further and Higher Education Act 1992. It is ranked among the Top 100 universities under 50 in the world; the university offers a range of disciplines, from Pharmacy, International relations and politics, to Mechanical Engineering, Criminology, Criminal Justice, among others. The Guardian University Guide 2018 ranked its Sports Science number one in England, while Criminology, Social Work, Graphic Design and Fashion and Textiles courses are all in the top 10 across all universities in the UK. Furthermore, 89% of its research conducted in Physics, 90% of its research in Allied Health Professions have been rated as world-leading or internationally excellent in the most recent Research Excellence Framework.
The University is a member of the University Alliance and The Channel Islands Universities Consortium. Alumni include Grayson Perry, Simon Armitage and Ben Fogle. Portsmouth was named the UK's most affordable city for students in the Natwest Student Living Index 2016. On Friday 4 May 2018, the University of Portsmouth was revealed as the main shirt sponsor of Portsmouth F. C. for the 2018–19, 2019–20 and 2020–21 seasons. The history of the university dates to 1908, when the Park building opened as a Municipal college and public library; the focus was on engineering. The roots of the University can be traced back further to the Portsmouth and Gosport School of Science and the Arts. Shortly after in the year of 1911 a Student Union was established. From 1945 to 1960 the college diversified its syllabus adding arts and humanities subjects after World War II, in response to a decline in the need for engineering skills; this did not hinder its expansion or reputation, as from 1960 to 1980 it opened the Frewen library, gained Polytechnic status and became one of the largest polytechnics by the late 1980s.
On 7 July 1992 the inauguration of the University of Portsmouth was celebrated at a ceremony at Portsmouth Guildhall. As a new university, it could validate its own degrees, under the provision of the Further and Higher Education Act 1992; the university is split between the University Quarter, centred around the Portsmouth Guildhall area, the Langstone Campus. Langstone is the smaller of the two campuses, located in Milton on the eastern edge of Portsea Island; the campus overlooks Langstone Harbour and it is home to the university's sports grounds. It houses a restaurant for the students and provides accommodation for 565 students in three halls of residence: Queen Elizabeth Queen Mother, Trust Hall and Langstone Flats. Langstone Campus used to be home of the University's School of Languages and Area Studies, which has since moved into Park Building in the University Quarter; the University Quarter is a collection of university buildings located around the centre of the city. This area contains most of the university's teaching facilities and nearly all of the Student Halls of residence (except the Langstone student village and two halls located on Southsea Terrace.
The University Library was extended in 2006 at a cost of £11 million. It was opened by the crime writer P. D. James; the University has recently invested in the Faculty of Science, in particular by renovating the aluminium-clad main building, St Michael's, adjacent to James Watson Hall, named after the co-discoverer of the structure of DNA. A new faculty called "Creative and Cultural Industries" was opened in September 2006, it provides a unique environment in which all aspects of creative thinking will flourish and develop by combining creative schools from across the university. On 7 June 2013, the University of Portsmouth announced its partnership with the Military Technological College of Oman; this involves the University of Portsmouth providing academic guidance and academic accreditation for the education of 4,200 students with technical roles in armed services and a few civilian employers in the Sultanate of Oman. This has been criticised by the student Amnesty International Society and by Campaign Against the Arms Trade who consider Oman an authoritarian regime to use military capabilities on their own citizens or in regional conflicts.
Portsmouth is formally headed by the Chancellor Karen Blackett. The Chancellor is a ceremonial role; this includes Pro Vice-Chancellors, the Director of Finance and the Deans of faculties, together with the Chief Operating Officer, the Director of Human Resources and the University Secretary and Clerk. The University of Portsmouth is composed of five faculties divided into 29 departments: The University of Portsmouth is worth £1.1 billion to the British economy and brings £476 million to the city, an independent assessment in 2017 has shown. Portsmouth offers more than 200 undergraduate degrees and 150 postgraduate degrees, as well as 65 research degree programs; the university validated BSc degrees in Acupuncture and MSc courses in Traditional Chinese medicine that were carried out by the London College of Traditional Acupuncture and Oriental Medicine, a private education provider that collapsed in early 2011. Over 60% of research submitted by the University to REF2014 was rated as world-
The Grandes Écoles of France are higher education establishments that are outside the main framework of the French public university system. The Grandes Écoles are selective and prestigious institutions. Most Grandes Écoles select students for admission as graduates of bachelor degree programs, while others select students at the third year of undergraduate-level study, based chiefly on the student's national ranking in competitive written and oral exams. Candidates for the national exams have completed two years of dedicated preparatory classes for admission. Grandes écoles differ from public universities in France, which have a legal obligation to accept in the first year of undergraduate studies all candidates of the region who hold a corresponding baccalauréat.. Grande écoles do not have large student bodies: most give admission to few hundred students each year. Arts et Métiers ParisTech has the largest student population, with 6,000 students. Studying in some grandes écoles after passing the competitive exams is considered part of public service.
Students pay low or no fees, are paid monthly stipends by some institutions. They are committed to ten years of public service; the business schools charge higher fees. Economically disadvantaged students in grandes écoles may have access to grants and subsidies, just as they would at a public university; the phrase'Grande École' originated in 1794 after the French Revolution, when the National Convention created the École normale supérieure, the mathematician Gaspard Monge and Lazare Carnot created the École centrale des travaux publics and the abbot Henri Grégoire created the Conservatoire national des arts et métiers. The model was the military academy at Mézières, of which Monge was an alumnus; the system of competitive entry was a means to open up higher education to more candidates based on merit. Some schools included in the category have roots in the 17th and 18th century and are older than the phrase'Grande École', dated 1794, their forerunners were schools aimed at graduating civil servants, such as technical officers, mine supervisors and road engineers, shipbuilding engineers.
Five military engineering academies and graduate schools of artillery were established in the 17th century in France, such as the école de l'artillerie de Douai and the école du génie de Mézières, wherein mathematics and sciences were a major part of the curriculum taught by first-rank scientists such as Pierre-Simon Laplace, Charles Étienne Louis Camus, Étienne Bézout, Sylvestre-François Lacroix, Siméon Denis Poisson, Gaspard Monge. In 1802 Napoleon created the École Spéciale Militaire de Saint Cyr, considered a Grande École, although it trains only army officers. During the 19th century, a number of higher education Grandes écoles were established to support industry and commerce, such as École Nationale Supérieure des Mines de Saint-Étienne in 1816, Ecole Supérieure de Commerce de Paris, L'institut des sciences et industries du vivant et de l'environnement in 1826, École Centrale des Arts et Manufactures in 1829. Between 1832 and 1870, the Central School of Arts and Manufactures produced 3,000 engineers, served as a model for most of the industrialized countries.
Until 1864, a quarter of its students came from abroad. Conversely, the quality of French technicians astonished southeastern Europe, the Near East, Belgium; the system of grandes écoles expanded, enriched in 1826 by the Ecole des Eaux et Forêts at Nancy, the Ecole des Arts Industriels at Lille in 1854, the Ecole Centrale Lyonnaise in 1857, the National Institute of Agronomy, reconstituted in 1876 after a fruitless attempt between 1848 and 1855. The training of the lower grades of staff, who might today be called ‘production engineers’, was assured to an greater extent by the development of Ecoles d’Arts et métiers, of which the first was established at Châlons-sur-Marne in 1806 and the second at Angers in 1811, with a third at Aix-en-Provence in 1841; each had room for 300 pupils. There is no doubt that in the 1860s France had the best system of higher technical and scientific education in Europe. During the latter part of the 19th century and in the 20th century, more Grandes écoles were established for education in businesses as well as newer fields of science and technology, including Rouen Business School in 1871, Sciences Po Paris in 1872, École nationale supérieure des télécommunications, Hautes Études Commerciales, Ecole Supérieure des Sciences Economiques et Commerciales École supérieure d'électricité and Supaero.
Since France has had a unique dual higher education system, with small and middle-sized specialized graduate schools operating alongside the traditional university system. Some fields of study are nearly exclusive to one part of this dual system, such as medicine in universités only, o
Compressible flow is the branch of fluid mechanics that deals with flows having significant changes in fluid density. Gases display such behaviour. While all flows are compressible, flows are treated as being incompressible when the Mach number is less than 0.3. The study of compressible flow is relevant to high-speed aircraft, jet engines, rocket motors, high-speed entry into a planetary atmosphere, gas pipelines, commercial applications such as abrasive blasting, many other fields; the study of gas dynamics is associated with the flight of modern high-speed aircraft and atmospheric reentry of space-exploration vehicles. At the beginning of the 19th century, investigation into the behaviour of fired bullets led to improvement in the accuracy and capabilities of guns and artillery; as the century progressed, inventors such as Gustaf de Laval advanced the field, while researchers such as Ernst Mach sought to understand the physical phenomenon involved through experimentation. At the beginning of the 20th century, the focus of gas dynamics research shifted to what would become the aerospace industry.
Ludwig Prandtl and his students proposed important concepts ranging from the boundary layer to supersonic shock waves, supersonic wind tunnels, supersonic nozzle design. Theodore von Kármán, a student of Prandtl, continued to improve the understanding of supersonic flow. Other notable figures contributed to the principles considered fundamental to the study of modern gas dynamics. Many others contributed to this field. Accompanying the improved conceptual understanding of gas dynamics in the early 20th century was a public misconception that there existed a barrier to the attainable speed of aircraft referred to as the "sound barrier." In truth, the barrier to supersonic flight was a technological one, although it was a stubborn barrier to overcome. Amongst other factors, conventional aerofoils saw a dramatic increase in drag coefficient when the flow approached the speed of sound. Overcoming the larger drag proved difficult with contemporary designs, thus the perception of a sound barrier. However, aircraft design progressed sufficiently to produce the Bell X-1.
Piloted by Chuck Yeager, the X-1 achieved supersonic speed in October 1947. Two parallel paths of research have been followed in order to further gas dynamics knowledge. Experimental gas dynamics undertakes wind tunnel model experiments and experiments in shock tubes and ballistic ranges with the use of optical techniques to document the findings. Theoretical gas dynamics considers the equations of motion applied to a variable-density gas, their solutions. Much of basic gas dynamics is analytical, but in the modern era Computational fluid dynamics applies computing power to solve the otherwise-intractable nonlinear partial differential equations of compressible flow for specific geometries and flow characteristics. There are several important assumptions involved in the underlying theory of compressible flow. All fluids are composed of molecules, but tracking a huge number of individual molecules in a flow is unnecessary. Instead, the continuum assumption allows us to consider a flowing gas as a continuous substance except at low densities.
This assumption provides a huge simplification, accurate for most gas-dynamic problems. Only in the low-density realm of rarefied gas dynamics does the motion of individual molecules become important. A related assumption is the no-slip condition where the flow velocity at a solid surface is presumed equal to the velocity of the surface itself, a direct consequence of assuming continuum flow; the no-slip condition implies that the flow is viscous, as a result a boundary layer forms on bodies traveling through the air at high speeds, much as it does in low-speed flow. Most problems in incompressible flow involve only two unknowns: pressure and velocity, which are found by solving the two equations that describe conservation of mass and of linear momentum, with the fluid density presumed constant. In compressible flow, the gas density and temperature become variables; this requires two more equations in order to solve compressible-flow problems: an equation of state for the gas and a conservation of energy equation.
For the majority of gas-dynamic problems, the simple Ideal gas law is the appropriate state equation. Fluid dynamics problems have two overall types of references frames, called Eulerian; the Lagrangian approach follows a fluid mass of fixed identity. The Eulerian reference frame, in contrast, does not move with the fluid. Rather it is a fixed control volume that fluid flows through; the Eulerian frame is most useful in a majority of compressible flow problems, but requires that the equations of motion be written in a compatible format. Although space is known to have 3 dimensions, an important simplification can be had in describing gas dynamics mathematically if only one spatial dimension is of primary importance, hence 1-dimensional flow is assumed; this works well in duct and diffuser flows where the flow properties change in the flow direction rather than perpendicular to the flow. However, an important class of compressible flows, including the external flow over bodies traveling at high speed, requires at least a 2-dimensional treatment.
When all 3 spatial dimensions and the time dimension as well are important, we reso
The École Navale is the French naval academy, in charge of the education of the officers of the French Navy. They are educated at the academy for responsibilities onboard surface ships and submarines, in French Naval Aviation, with the fusiliers marins and commandos, on the general staff; the École Navale and its research institute are in Lanvéoc-Poulmic, south of the roadstead of Brest. The academy was founded by order of King Louis-Philippe; the academy was based on ships, anchored in the harbour of Brest, such as the Borda, hence the nickname of "Bordache" given to the students. In 1914, the École Navale was transferred ashore in Brest; the school was destroyed by Allied bombing raids during World War II, was moved to nearby Lanvéoc-Poulmic, on the opposite side of the bay of Brest. The academy remained in this location after the war, was inaugurated by Charles de Gaulle in 1965; the École Navale, created in 1830, was located onboard vessels harboured in Brest all of which were nicknamed Borda.
The first vessel to house the École Navale was named Orion. This ship had an inappropriate name for a naval academy, so it was renamed Borda. In 1863, the academy was transferred to the Valmy in 1890, to the Intrépide, in 1913, to the Duguay-Trouin, a school vessel for those applying to the Navy between 1900 and 1912. With the exceptions of the Orion and the Duguay-Trouin, each of these vessels was still christened as Borda; the new pupils are boarded from one day before the others. Crammed like sheep in a gunboat, they were bouncy and happy while launching a goodbye to their families; as soon as arrived, they were sorted, undressed in order to give them the white blouse and linen trousers. Their hair was shorn. Two days the parents were authorised onboard for the opening mass for the new cadets. Flags were placed around the altar, a single seat was reserved for the "Pope", the nickname of the captain commanding the academy; the parents took place on bench, the pupils entered, the senior ones first, tiding themselves on the sides, the new cadets in their new suit under the quip of the others who were screaming "Caillou!
Caillou!" to recognize the new cadets. This was followed by the first formal dinner of the new students. A traditional ceremony onboard the Borda was the presentation and delivery of the sword to the son by his "baille" father, for the first day of outing. In the spring, when the first outing in dinghy occurred, another consecration took place, this of baptism of the new cadets by the senior cadets of the academy, as the latter throw water buckets upon the former; the École Navale is traditionally called "La Baille". Its jargon comes principally from maritime slang. Like every "Grande Ecole", the jargon is wide-used among its student body. For example, the commander in second is the "widow"; the elephants, or the "pékins", are the civilians. The "chafustard" is the mechanic; the songs of the board are crude, but of high musical and literary standard. Nowadays, the student body uses some expressions coming from other military academies and from military high schools; the standard reference book about the jargon at "La Baille" was written by Commander Roger Coindeau, illustrated by Luc-Marie Bayle.
All this will not impede the future Navy officers to work hard. It is the first step. Comes the climbing of the second hune, little by little, everyone gets accustomed not to have dizziness, but to run on the footboard stretched beneath each yardarm, to unfurl the sail. All this is commanded by a whistle. If the job of topsman had become unuseful with the modern war boats, it was still taught to the student-officers, in order for them to be able to bring back a catch in time of war with its sails, because it was part of the old traditions of the French Navy; the two years of school were well filled up with everything that a Navy officer had to learn: rowing, the machines, armed drill and weapons instruction, combat training aboard or onshore, signal flags, vessel maintenance, superior mathematics, hydrography, English language, a lot more. At the 3rd year of studies, the 2nd classmen left the Borda for their training cruises to various parts of the world. In the beginning of the 20th century, a project to move the Ecole Naval, to the ground, had made its way.
The chosen place was in the district of Recouvrance. The project failed due to a lack of money; however the school settled in 1915 in buildings built in Laninon situated in Recouvrance, as the First World War was raging. Work for the campus began November 14, 1929 and was presided by Georges Leygues, minister of the Navy, the school was inaugurated on 30 May 1936 by Albert Lebrun, President of the Republic. Regardless of the grounding of the school, the final year of formation and training at sea has been preserved in the form of traditional cruisi
France the French Republic, is a country whose territory consists of metropolitan France in Western Europe and several overseas regions and territories. The metropolitan area of France extends from the Mediterranean Sea to the English Channel and the North Sea, from the Rhine to the Atlantic Ocean, it is bordered by Belgium and Germany to the northeast and Italy to the east, Andorra and Spain to the south. The overseas territories include French Guiana in South America and several islands in the Atlantic and Indian oceans; the country's 18 integral regions span a combined area of 643,801 square kilometres and a total population of 67.3 million. France, a sovereign state, is a unitary semi-presidential republic with its capital in Paris, the country's largest city and main cultural and commercial centre. Other major urban areas include Lyon, Toulouse, Bordeaux and Nice. During the Iron Age, what is now metropolitan France was inhabited by a Celtic people. Rome annexed the area in 51 BC, holding it until the arrival of Germanic Franks in 476, who formed the Kingdom of Francia.
The Treaty of Verdun of 843 partitioned Francia into Middle Francia and West Francia. West Francia which became the Kingdom of France in 987 emerged as a major European power in the Late Middle Ages following its victory in the Hundred Years' War. During the Renaissance, French culture flourished and a global colonial empire was established, which by the 20th century would become the second largest in the world; the 16th century was dominated by religious civil wars between Protestants. France became Europe's dominant cultural and military power in the 17th century under Louis XIV. In the late 18th century, the French Revolution overthrew the absolute monarchy, established one of modern history's earliest republics, saw the drafting of the Declaration of the Rights of Man and of the Citizen, which expresses the nation's ideals to this day. In the 19th century, Napoleon established the First French Empire, his subsequent Napoleonic Wars shaped the course of continental Europe. Following the collapse of the Empire, France endured a tumultuous succession of governments culminating with the establishment of the French Third Republic in 1870.
France was a major participant in World War I, from which it emerged victorious, was one of the Allies in World War II, but came under occupation by the Axis powers in 1940. Following liberation in 1944, a Fourth Republic was established and dissolved in the course of the Algerian War; the Fifth Republic, led by Charles de Gaulle, remains today. Algeria and nearly all the other colonies became independent in the 1960s and retained close economic and military connections with France. France has long been a global centre of art and philosophy, it hosts the world's fourth-largest number of UNESCO World Heritage Sites and is the leading tourist destination, receiving around 83 million foreign visitors annually. France is a developed country with the world's sixth-largest economy by nominal GDP, tenth-largest by purchasing power parity. In terms of aggregate household wealth, it ranks fourth in the world. France performs well in international rankings of education, health care, life expectancy, human development.
France is considered a great power in global affairs, being one of the five permanent members of the United Nations Security Council with the power to veto and an official nuclear-weapon state. It is a leading member state of the European Union and the Eurozone, a member of the Group of 7, North Atlantic Treaty Organization, Organisation for Economic Co-operation and Development, the World Trade Organization, La Francophonie. Applied to the whole Frankish Empire, the name "France" comes from the Latin "Francia", or "country of the Franks". Modern France is still named today "Francia" in Italian and Spanish, "Frankreich" in German and "Frankrijk" in Dutch, all of which have more or less the same historical meaning. There are various theories as to the origin of the name Frank. Following the precedents of Edward Gibbon and Jacob Grimm, the name of the Franks has been linked with the word frank in English, it has been suggested that the meaning of "free" was adopted because, after the conquest of Gaul, only Franks were free of taxation.
Another theory is that it is derived from the Proto-Germanic word frankon, which translates as javelin or lance as the throwing axe of the Franks was known as a francisca. However, it has been determined that these weapons were named because of their use by the Franks, not the other way around; the oldest traces of human life in what is now France date from 1.8 million years ago. Over the ensuing millennia, Humans were confronted by a harsh and variable climate, marked by several glacial eras. Early hominids led a nomadic hunter-gatherer life. France has a large number of decorated caves from the upper Palaeolithic era, including one of the most famous and best preserved, Lascaux. At the end of the last glacial period, the climate became milder. After strong demographic and agricultural development between the 4th and 3rd millennia, metallurgy appeared at the end of the 3rd millennium working gold and bronze, iron. France has numerous megalithic sites from the Neolithic period, including the exceptiona