UK education system

Education in the United Kingdom is a devolved matter with each of the countries of the United Kingdom having separate systems under separate governments: the UK Government is responsible for education in England, the Scottish Government is responsible for education in Scotland, the Welsh Assembly Government is responsible for education in Wales and the Northern Ireland Executive is responsible for education in Northern Ireland. In each country, education, though not school attendance, is mandatory and attendance at primary and secondary is nearly universal, with most pupils attending state schools. However, there are major differences between the school systems in terms of the curriculum, examinations and final qualifications, as well as differences at University level in terms of the nature of some degrees and the issue of tuition fees.

For details of education in each country,

Wales education system

Education in Wales differs in certain respects from the systems used elsewhere in the United Kingdom. A significant number of students all over Wales are educated either wholly or largely through the medium of Welsh; lessons in the language are compulsory for all until the age of 16. Welsh medium education is available to all age groups through nurseries, schools, colleges and universities and in adult education. There are also plans to increase the number of Welsh medium schools.

Currently, demand has passed supply for education through the medium of Welsh especially in Cardiff and the surrounding South Wales Valleys. Some schools in South Wales are now having to turn Welsh students away as there are no spaces in the schools compared to the English schools where in some cases pupil levels are only reaching 50% capacity. In Cardiff, there are plans to close two English Schools and open two large Welsh schools. In Newport, there are now plans for the city to have its first Welsh medium secondary school, and there are also plans for Swansea and Llanelli to have more Welsh schools. This is in line with Welsh Assembly policy of having a totally bilingual Wales.

UAE edcation system

Provision of quality education in the United Arab Emirates began shortly after the establishment of the federation with the inception of the first university in Al Ayn, Abu Dhabi, the United Arab Emirates University. Since then, the country has progressed with efforts of ensuring high literacy rates, modern programs and women’s share in education. The UAE currently devotes approximately 25 percent of total federal government spending to education. Public education is free for male and female citizen children through the university level. Beginning in the academic year 2006–7, expatriate students may, for a fee, attend government schools. The UAE has one of the lowest pupil-to-teacher ratios (15:1) in the world. Education is compulsory through the ninth grade, although, according to the U.S. Department of State, this requirement is not enforced. Citizen children are required to attend gender-segregated schools through the sixth grade, the last grade of primary education. Primary school enrollment for males in 2006 stood at 85% and 82% of females. 97% of entrants reached the 5th grade.[1] Secondary school enrollment figures remained lower at 62% for males although higher for females at 66%.[2] In 2004–5 approximately 9.9 percent of students in grades one through five and 8.3 percent of students in grades six through nine did not complete their education; this rate rose to 9.3 percent in grades 10–12. According to the CIA World Factbook, total literacy under 15 years in 2003 reached 77.9% Between the ages of 15-24, males reached 98% literacy and women 96%.

In 2005, the United Nations Programme on Governance in the Arab Region rated the UAE a .79 on its Education Index. The Programme defines the Index as, “One of the three indices on which the human development index is build. It is based on the adult literacy rate and the combined gross enrolment ratio for primary, secondary and tertiary schools. Regionally, the countries scoring higher included the Occupied Palestinian Territories at .89; Libya, Lebanon and Kuwait at .87; Jordan and Bahrain at .86; and Saudi Arabia at .80. All of the countries ranked in the index reported a significantly higher number of phones per population than internet users, with the UAE claiming one hundred twenty eight versus twenty-nine. Internationally, the country with the highest rating was Australia with a .99 while Burkinafaso stood lowest at .27.

Despite not being among the highest rated on the Education Index, the UAE has made regionally significant achievements in ensuring women’s access to education. UNDP’s Millennium Development Goal No. 3, to “Promote Gender Equality and Empower Women” has reached its targeted levels of female participation in primary education and continues to increase.

Switzerland education system

The education system in Switzerland is very diverse, because the constitution of Switzerland delegates the authority for the school system to the cantons (Article 62). The Swiss constitution sets the foundations, namely that primary school is obligatory for every child and is free in public schools and that the confederation can run or support universities. Swiss people have voted on May 21, 2006 to reform the education system in one common program for all the cantons. Because of its diversity, there are many private international schools in Switzerland that encourage respect for all cultures.

The minimum age for primary school is about six years in all cantons but Obwalden, where it is five years and three months. Any boy or girl can take part in school if they choose to, but kids are separated depending on whether they speak French, German or Italian. Primary school continues until grade four or five, depending on the school.

At the end of primary school (or at the beginning of secondary school), pupils are separated according to their capacities in several (often three) sections. The best students are taught advanced classes to be prepared for further studies and the matura, while students who assimilate a little bit more slowly receive an education more adapted to their needs. In PISA science literacy assessment, 15-year-old students in Switzerland had the 16th highest average score of 57 countries.

The first university in Switzerland was founded in 1460 in Basel, with a faculty of medicine. This place has a long tradition of chemical and medical research in Switzerland. In total, there are 12 Universities in Switzerland; ten of them are managed by the cantons, while two federal institutes of technology, ETHZ in Zürich and EPFL in Lausanne, are under the responsibility of the federal state. In addition, there are various Universities of Applied Sciences which do not require a matura degree to study. Switzerland has the second highest rate of foreign students in tertiary education, after Australia.

Many Nobel prizes were awarded to Swiss scientists. More recently Vladimir Prelog, Heinrich Rohrer, Richard Ernst, Edmond Fischer, Rolf Zinkernagel and Kurt Wüthrich received nobel prizes in the sciences. In total, 113 Nobel Prize winners stand in relation to Switzerland and the Nobel Peace Price was awarded 9 times to organizations residing in Switzerland.[4] Geneva host the world's largest particle physics laboratory, the CERN. An other important research center is the Paul Scherrer Institute which belongs to the ETHZ.

South Korea education system

Education in South Korea is important for success and competition is consequently very heated and fierce.A centralized administration oversees the process for the education of children from kindergarten to the third and final year of high school. Mathematics, science, Korean, social studies, and English are generally considered to be the most important subjects.[citation needed] Sometimes physical education is not considered important as it is not regarded to be education and therefore many schools lack high-quality gymnasiums and varsity athletics.[citation needed] South Korea was the first country in the world to provide high-speed internet access from every primary, junior, and high school.

The school year is divided into two semesters. The first begins in the beginning of March and ends in mid-July; the second begins in late August and ends in mid-February. They have summer vacation from mid-July to late August, and winter vacation from late-December to early February, and also take a short vacation from mid-February to end of that month. The schedules are not rigidly standardized, however, and can vary from school to school.

Scotland Edcation system

Scotland has a long history of universal provision of public education, and the Scottish education system is distinctly different from other parts of the United Kingdom.

Traditionally, the Scottish system has emphasised breadth across a range of subjects, while the English, Welsh and Northern Irish systems have emphasised greater depth of education over a smaller range of subjects at secondary school level.

Following this, Scottish universities generally have courses a year longer (typically 4 years) than their counterparts elsewhere in the UK, though it is often possible for students to take more advanced specialised exams and join the courses at the second year. One unique aspect is that the ancient universities of Scotland issue a Master of Arts as the first degree in humanities.

The majority of schools are non-denominational, but as a result of the Education Act 1918, separate Roman Catholic state schools were also established. Catholic schools are fully funded by the Scottish Government and administered by the Education and Lifelong Learning Directorate. There are specific legal provisions to ensure the promotion of a Catholic ethos in such schools: applicants for positions in the areas of Religious Education, Guidance or Senior Management must be approved by the Roman Catholic Church in Scotland, which also appoints a chaplain to each of its schools. There is also one Jewish state primary school.

Qualifications at the secondary school and post-secondary (further education) level are provided by the Scottish Qualifications Authority, which is the national awarding and accrediting body in Scotland, and delivered through various schools, colleges and other centres. Political responsibility for education at all levels is vested in the Scottish Parliament and the Scottish Education and Enterprise, Transport and Lifelong Learning Departments

Russian Language

Russian (русский язык, transliteration: russkiy yazyk, Russian pronunciation: [ˈruskʲɪj jɪˈzɨk]) is the most geographically widespread language of Eurasia, the most widely spoken of the Slavic languages, and the largest native language in Europe. Russian belongs to the family of Indo-European languages and is one of three living members of the East Slavic languages, the others being Belarusian and Ukrainian (and possibly Rusyn, normally considered a dialect of Ukrainian).

Written examples of Old East Slavonic are attested from the 10th century onwards. Today Russian is widely used outside Russia. Over a quarter of the world's scientific literature is published in Russian.Russian is also a necessary accessory of world communications systems (broadcasts, air- and space communication, etc). Because of the status of the Soviet Union as a superpower, Russian had great political importance in the 20th century. Hence, the language is one of the six official languages of the United Nations.

Russian distinguishes between consonant phonemes with palatal secondary articulation and those without, the so-called soft and hard sounds. This distinction is found between pairs of almost all consonants and is one of the most distinguishing features of the language. Another important aspect is the reduction of unstressed vowels, which is somewhat similar to that of English. Stress, which is unpredictable, is not normally indicated orthographically though, according to the Russian Language Institute of the Russian Academy of Sciences, an optional acute accent (знак ударения) may, and sometimes should, be used to mark stress (such as to distinguish between otherwise identical words or to indicate the proper pronunciation of uncommon words or names).

Russian education system

Education in Russia is provided predominantly by the state and is regulated by the federal Ministry of Education. Regional authorities regulate education within their jurisdictions within the prevailing framework of federal laws. In 2004 state spending for education amounted to 3.6% of GDP, or 13% of consolidated state budget.Private institutions account for 1% of pre-school enrollment, 0.5% of elementary school enrollment and 17% of university-level students.

Before 1990 the course of school training in Soviet Union was 10-years, but at the end of 1990 the 11-year course has been officially entered. Education in state-owned secondary schools is free; first tertiary (university level) education is free with reservations: a substantial share of students is enrolled for full pay. Male and female students have nearly equal shares in all stages of education,

except tertiary education where women lead with 57%.

The literacy rate in Russia, according to the 2002 census, is 99.4% (99.7% men, 99.2% women).

16.0% of population over 15 years of age (17.6 million) have tertiary (undergradute level or higher) education; 47.7% have completed secondary education (10 or 11 years); 26.5% have completed middle school (8 or 9 years) and 8.1% have elementary education. Highest rates of tertiary education, 24.7% are recorded among women aged 35–39 years (compared to 19.5% for men of the same age bracket).

Oxford University

The University of Oxford (informally Oxford University, or simply Oxford), located in the City of Oxford, Oxfordshire, Great Britain, is the oldest university in the English-speaking world. It is also regarded as one of the world's leading academic institutions and best university in the UK according to all recent League tables of British universities.The name is sometimes abbreviated as Oxon. in post-nominals (from the Latin Oxoniensis), although Oxf is sometimes used in official publications. The University has 38 independent colleges and six permanent private halls.

The university traces its roots back to at least 1167, although the exact date of foundation remains unclear, and there is evidence of teaching there as far back as the 10th century. After a dispute between students and townsfolk broke out in 1209, some of the academics at Oxford fled north-east to the town of Cambridge, where the University of Cambridge was founded. The two universities (collectively known as "Oxbridge") have since had a long history of competition with each other.

The University of Oxford is a member of the Russell Group of research-led British universities, the Coimbra Group (a network of leading European universities), the League of European Research Universities, International Alliance of Research Universities and is also a core member of the Europaeum. Academically, Oxford is consistently ranked in the world's top 10 universities.For more than a century, it has served as the home of the Rhodes Scholarship, which brings highly accomplished students from a number of countries to study at Oxford as postgraduates.

Macau Education system

Most of the schools in Macau are private or subsidized schools. There are only a few government or public schools, in which Portuguese is used as a medium of instruction or taken as a compulsory subject in Macau. A basic ten-year compulsory, free education, is offered to those students who have been enrolled in the schools which have met certain requirements stipulated by the government.

Moreover, the majority of the schools in Macau are so-called grammar schools, which offer language learning, mathematics, science subjects, social studies, etc. to the students. There are only a few vocational schools in Macau, offering technical subjects such as car repairing, electronics, electrical engineering, etc.

As prescribed by the Basic Law of Macau Chapter VI Article 121, the Government of Macau shall, on its own, formulate policies on education, including policies regarding the educational system and its administration, the language of instruction, the allocation of funds, the examination system, the recognition of educational qualifications and the system of academic awards so as to promote educational development. The government shall also in accordance with law, gradually institute a compulsory education system. Community organisations and individuals may, in accordance with law, run educational undertakings of various kinds.

Ireland education

Education in Northern Ireland differs slightly from systems used elsewhere in the United Kingdom, though it is more similar to that used in England and Wales than it is to Scotland. A child's age on 1 July determines the point of entry into the relevant stage of education unlike England and Wales where it is the 1 September. Northern Ireland's results at GCSE and A-Level are consistently top in the UK. At A-Level, one third of students in Northern achieved A grades in 2007, compared with England and Wales.

Hong Kong Education

Education in Hong Kong has a similar system to that of the United Kingdom, in particular the English education system of Hong Kong was modernised by the British in 1861. The system can be described as extremely competitive by global standards.

Harvard University

Harvard University (incorporated as The President and Fellows of Harvard College) is a private university located in Cambridge, Massachusetts, and a member of the Ivy League. Founded in 1636 by the colonial Massachusetts legislature, Harvard is the oldest institution of higher learning in the United States. It is also the first and oldest corporation in North America. Administratively, Harvard comprises ten primary academic units.

Initially called "New College" or "the college at New Towne", the institution was renamed Harvard College on March 13, 1639. It was named after a young clergyman named John Harvard, who bequeathed the College his library of four hundred books and £779 (which was half of his estate). The earliest known official reference to Harvard as a "university" occurs in the new Massachusetts Constitution of 1780.

During his 40-year tenure as Harvard president (1869–1909), Charles William Eliot radically transformed Harvard into the pattern of the modern research university. Eliot's reforms included elective courses, small classes, and entrance examinations. The Harvard model influenced American education nationally, at both college and secondary levels.

Harvard is consistently ranked at or near the top of international college and university rankings,and has the second-largest financial endowment of any non-profit organization (behind the Bill & Melinda Gates Foundation), standing at $28.8 billion as of 2008. Harvard and Yale have been rivals in academics, rowing, and football for most of their history, competing annually in The Game and the Harvard-Yale Regatta.

UK exams

Examination boards in the United Kingdom (sometimes called awarding bodies or examining groups) are the examination boards responsible for setting and awarding secondary education level qualifications, such as GCSEs, Standard Grades, A Levels, Highers and vocational qualifications, to students in the United Kingdom.

Broadly speaking, the UK has (and has always had) two separate school systems: one for England, Wales and Northern Ireland and one for Scotland. As a result, two separate sets of exam boards have developed.

England Education System

Education in England is overseen by the Department for Children, Schools and Families and the Department for Business, Innovation and Skills. At a local level the local authorities take responsibility for implementing policy for public education and state schools.

Full-time education is compulsory for all children aged between 5 and 16 (inclusive). Students may then continue their secondary studies for a further two years (sixth form), leading most typically to an A level qualification, although other qualifications and courses exist, including GNVQ and the International Baccalaureate. The leaving age for compulsory education was raised to 18 by the Education and Skills Act 2008. The change will take effect in 2013 for 17 year olds and 2015 for 18 year olds.State-provided schools are free of charge to students, and there is also a tradition of independent schooling, but parents may choose to educate their children by any suitable means.

Higher education typically begins with a 3-year Bachelor's Degree. Postgraduate degrees include Master's Degrees, either taught or by research, and Doctor of Philosophy, a research degree that usually takes at least 3 years. Universities require a Royal Charter in order to issue degrees, and all but one are financed by the state with a low level of fees for students.

Dubai Education System

Education in Dubai encompasses the many levels of primary, secondary and collegiate education catering to various ethnic and linguistic groups. The school system in Dubai does not differ from the school system in the United Arab Emirates. There are many public and private schools serving Emiratis and expatriates. The medium of instruction in public schools is Arabic with emphasis on English as a second language, While most of the private schools use English as their medium of instruction. The Ministry of Education of the United Arab Emirates is responsible for school's accreditation. The Dubai Education Council was established in July 2005 to develop the education sector in Dubai.Annual fees for all schools vary greatly from free for public schools to a few thousand or tens of thousands dirhams per year for private schools.

China Education

The People's Republic of China has a nationwide system of public education, which includes primary schools, middle schools (lower and upper), and universities. Nine years of education is technically compulsory for all Chinese students.

Education in China is the responsibility of the Ministry of Education. The education system provides free primary education for six years (some provinces may have 5 years for primary school but 4 years for middle school) , starting at age six or seven, followed by six years of secondary education for ages 12 to 18. At this level, there are three years of middle school and three years of high school. The Ministry of Education reported a 99 percent attendance rate for primary school and an 80 percent rate for both primary and middle schools. Since free higher education was abolished in 1985, applicants to colleges and universities competed for scholarships based on academic ability. Private schools have been allowed since the early 1980s. The population has had on average only 6.2 years of schooling, but in 1986 the goal of nine years of compulsory education by 2000 was established.

The United Nations Development Programme reported that in 2003 China had 116,390 kindergartens with 613,000 teachers and 20 million students. At that time, there were 425,846 primary schools with 5.7 million teachers and 116.8 million students. General secondary education had 79,490 institutions, 4.5 million teachers, and 85.8 million students. There also were 3,065 specialized secondary schools with 199,000 teachers and 5 million students. Among these specialized institutions were 6,843 agricultural and vocational schools with 289,000 teachers and 5.2 million students and 1,551 special schools with 30,000 teachers and 365,000 students.

China has already pulled off one of the most remarkable expansions of education in modern times, increasing the number of undergraduates and people who hold doctoral degrees fivefold in 10 years.In 2003 China supported 1,552 institutions of higher learning (colleges and universities) and their 725,000 professors and 11 million students (see List of universities in the People's Republic of China). While there has been intense competition for admission to China’s colleges and universities among college entrants, Beijing and Tsinghua universities and more than 100 other National Key Universities that have been the most sought after.

In one generation, China has rapidly increased the proportion of its college-age population in higher education, to roughly 20 percent in 2005 from 1.4 percent in 1978. , China is producing 450,000 new undergraduates a year in engineering alone, along with 50,000 engineering graduates with masters' degrees and 8,000 Ph.D's.

The total literacy rate in China was 90.8% (male 95.1%; female 86.5%), based on 2002 estimates.

British English

British English, or UK English (BrE, BE, en-GB, is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere.There is confusion whether the term refers to English as spoken in the British Isles or to English as spoken in Great Britain, though in the case of Ireland, there are further distinctions peculiar to Hiberno-English.

There are slight regional variations in formal written English in the United Kingdom (for example, although the words wee and little are interchangeable in some contexts, one is more likely to see wee written by someone from northern Britain or from Northern Ireland than by someone from Southern England or Wales). Nevertheless, there is a meaningful degree of uniformity in written English within the United Kingdom, and this could be described as "British English". The forms of spoken English, however, vary considerably more than in most other areas of the world where English is spoken[citation needed] and a uniform concept of "British English" is therefore more difficult to apply to the spoken language. According to Tom McArthur in the Oxford Guide to World English (p. 45), "[f]or many people...especially in England [the phrase British English] is tautologous," and it shares "all the ambiguities and tensions in the word British, and as a result can be used and interpreted in two ways, more broadly or more narrowly, within a range of blurring and ambiguity".

American English

American English (variously abbreviated AmE, AE, AmEng, USEng, en-US, also known as United States English or U.S. English, is a set of dialects of the English language used mostly in the United States. Approximately two thirds of native speakers of English live in the United States.

English is the most common language in the United States. Though the U.S. federal government has no official language, English is considered the de facto language of the United States due to its widespread use. English has been given official status by 30 of the 50 state governments.

The use of English in the United States was inherited from British colonization. The first wave of English-speaking settlers arrived in North America in the 17th century. During that time, there were also speakers in North America of Spanish, French, Dutch, German, Norwegian, Swedish, Scots, Welsh, Irish, Scottish Gaelic, Finnish, Russian (Alaska) and numerous Native American languages.

American Education System

Education in the United States is mainly provided by the public sector, with control and funding coming from three levels: federal, state, and local. School attendance is mandatory and nearly universal at the primary and secondary levels (known inside the United States as the elementary and high school levels). At these levels, school curricula, funding, teaching, and other policies are set through locally elected school boards with jurisdiction over school districts. School districts are usually separate from other local jurisdictions, with independent officials and budgets. Educational standards and standardized testing decisions are usually made by state governments.

The ages for compulsory education vary by state, beginning at ages five to eight and ending at the ages of fourteen to eighteen.A growing number of states are now requiring school attendance until the age of 18.

Compulsory education requirements can generally be satisfied by attending public schools, state-certified private schools, or an approved home school program. In most public and private schools, education is divided into three levels: elementary school, junior high school (often called middle school), and high school. In almost all schools at these levels, children are divided by age groups into grades, ranging from kindergarten (followed by first grade) for the youngest children in elementary school, up to twelfth grade, which is the final year of high school. The exact age range of students in these grade levels varies slightly from area to area.

Post-secondary education, better known as "college" in the United States, is generally governed separately from the elementary and high school system, and is described in a separate section below.

In the year 2000, there were 76.6 million students enrolled in schools from kindergarten through graduate schools. Of these, 72 percent aged 12 to 17 were judged academically "on track" for their age (enrolled in school at or above grade level). Of those enrolled in compulsory education, 5.2 million (10.4 percent) were attending private schools. Among the country's adult population, over 85 percent have completed high school and 27 percent have received a bachelor's degree or higher. The average salary for college or university graduates is greater than $51,000, exceeding the national average of those without a high school diploma by more than $23,000, according to a 2005 study by the U.S. Census Bureau.While the United States presently leads the world with over 5,000 Montessori schools, the People's Republic of China (PRC) has expressed ambitions to replace much of their school system with the Montessori method's pedagogy. As part of a trial run towards achieving this objective, the PRC Minister of Education called for 1,000 teachers to receive certification from the Association Montessori Internationale in 2007. The United States Department of Education has no formal plans to compete against China on similar initiatives at this time.

The country has a reading literacy rate at 98% of the population over age 15, while ranking below average in science and mathematics understanding compared to other developed countries.[6] In 2008, there was a 77% graduation rate from high school, below most developed countries.

The poor performance has pushed public and private efforts such as the No Child Left Behind Act. In addition, the ratio of college-educated adults entering the workforce to general population (33%) is slightly below the mean of other developed countries (35%)[8] and rate of participation of the labor force in continuing education is high.[9] A 2000s study by Jon Miller of Michigan State University concluded that "A slightly higher proportion of American adults qualify as scientifically literate than European or Japanese adults".

The Upper Atmosphere Research Satellite (UARS) is an orbital observatory whose mission is to study the Earth’s atmosphere, particularly the protective ozone layer.

The 5900 kg (13,000 lb) satellite was launched during Space Shuttle mission STS-48 in 1991. The original mission life was to be three years. As of June 2005, six of the ten instruments were still operational. UARS orbits at an altitude of 375 miles with an orbital inclination of 57 degrees.

A final orbit lowering burn, followed by the "passivation" of the Satellite's systems was performed in early December, 2005.

Spacecraft

A spacecraft is a craft or machine designed for spaceflight. On a sub-orbital spaceflight, a spacecraft enters space then returns to the Earth. For an orbital spaceflight, a spacecraft enters a closed orbit around the planetary body. Spacecraft used for human spaceflight carry people on board as crew or passengers. Spacecraft used for robotic space missions operate either autonomously or telerobotically. Robotic spacecraft that leave the vicinity of the planetary body are space probes. Robotic spacecraft that remain in orbit around the planetary body are artificial satellites. Starships, which are built for interstellar travel, are so far a theoretical concept only.

Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and space tourism. Spacecraft and space travel are common themes in works of science fiction.

Space

Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction.Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of the boundless four-dimensional continuum known as spacetime. In mathematics spaces with different numbers of dimensions and with different underlying structures can be examined. The concept of space is considered to be of fundamental importance to an understanding of the universe although disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework.

Many of the philosophical questions arose in the 17th century, during the early development of classical mechanics. In Isaac Newton's view, space was absolute - in the sense that it existed permanently and independently of whether there were any matter in the space.Other natural philosophers, notably Gottfried Leibniz, thought instead that space was a collection of relations between objects, given by their distance and direction from one another. In the 18th century, Immanuel Kant described space and time as elements of a systematic framework which humans use to structure their experience.

In the 19th and 20th centuries mathematicians began to examine non-Euclidean geometries, in which space can be said to be curved, rather than flat. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean space provides a better model for explaining the existing laws of mechanics and optics.

Siesmology

Seismology (from Greek σεισμός, seismos, "earthquake"; and -λόγος, -logia, as a whole "Talking about earthquakes") is the scientific study of earthquakes and the propagation of elastic waves through the Earth. The field also includes studies of earthquake effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic, atmospheric, and artificial processes (such as explosions). A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of earth motion as a function of time is called a seismogram.

Ribonucleic acid (RNA)

Ribonucleic acid (RNA) is a type of molecule that consists of a long chain of nucleotide units. Each nucleotide consists of a nitrogenous base, a ribose sugar, and a phosphate. RNA is very similar to DNA, but differs in a few important structural details: in the cell, RNA is usually single-stranded, while DNA is usually double-stranded; RNA nucleotides contain ribose while DNA contains deoxyribose (a type of ribose that lacks one oxygen atom); and RNA has the base uracil rather than thymine that is present in DNA.

RNA is transcribed from DNA by enzymes called RNA polymerases and is generally further processed by other enzymes. RNA is central to the synthesis of proteins. Here, a type of RNA called messenger RNA carries information from DNA to structures called ribosomes. These ribosomes are made from proteins and ribosomal RNAs, which come together to form a molecular machine that can read messenger RNAs and translate the information they carry into proteins. There are many RNAs with other roles – in particular regulating which genes are expressed, but also as the genomes of most viruses.

Psychology

Psychology (Greek: Ψυχολογία, lit. "study of the mind", from ψυχή psykhē "breath, spirit, soul"; and -λογία, -logia "study of" is an academic and applied discipline involving the systematic, and often scientific, study of human mental functions and behavior. Occasionally, in addition or opposition to employing the scientific method, it also relies on symbolic interpretation and critical analysis, although it often does so less prominently than other social sciences such as sociology. Psychologists study such phenomena as perception, cognition, emotion, personality, behavior and interpersonal relationships. Some, especially depth psychologists, also study the unconscious mind.

Psychological knowledge is applied to various spheres of human activity, including issues related to everyday life—such as family, education and employment—and to the treatment of mental health problems. Psychologists attempt to understand the role of mental functions in individual and social behavior, while also exploring the underlying physiological and neurological processes. Psychology includes many sub-fields of study and applications concerned with such areas as human development, sports, health, industry, media and law. Psychology incorporates research from the natural sciences, social sciences and humanities. A professional theorist or practitioner of psychology is called a psychologist

Platinum

Platinum (pronounced /ˈplætɨnəm/) is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is in Group 10 of the periodic table of elements. A dense, malleable, ductile, precious, gray-white transition metal, platinum is resistant to corrosion and occurs in some nickel and copper ores along with some native deposits. Platinum is used in jewelry, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry, and catalytic converters. Platinum bullion has the ISO currency code of XPT. Platinum is a commodity with a value that fluctuates according to market forces. On June 5, 2009, Platinum was worth $1263.00 per troy ounce (approximately $40.09 per gram).

Morphology

The term morphology in biology refers to form, structure and configuration of an organism.This includes aspects of the outward appearance (shape, structure, colour, pattern) as well as the form and structure of the internal parts like bones and organs. This is in contrast to physiology, which deals primarily with function.

Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. It can be subdivided into two distinct branches: anatomy is the study of the structure and internal organs of an organism. The study of the external appearance of an organism is called eidonomy, but while predominant early in the history of biology it is little studied in particular anymore as it is ripe with the effects of convergent evolution. It thus yields less new information about organisms than anatomy, and therefore the external appearance of lifeforms is usually studied as part of general investigations in morphology, e.g. in the context of phylogenetic research.

Also in use is the term "gross morphology", which refers to the prominent or principal aspects of an organism or taxon's morphology. A description of an organism's gross morphology would include, for example, its overall shape, overall colour, main markings etc. but not finer details.

Most taxa differ morphologically from other taxa. Typically, closely related taxa differ much less than more distantly related ones, but there are exceptions to this. Cryptic species are species which look very similar, or perhaps even outwardly identical, but are reproductively isolated. Conversely, sometimes unrelated taxa acquire similar appearance through convergent evolution or even through mimicry. A further problem with relying on morphological data is that what may appear, morphologically speaking, to be two distinct species, may in fact be shown by DNA analysis to be a single species

Missile

A guided missile is a self-propelled projectile used as a weapon. Missiles are typically propelled by rockets or jet engines. Missiles generally have one or more explosive warheads, although other weapon types may also be used.

Meteorology

Meteorology (from Greek μετέωρος, metéōros, "high in the sky"; and -λογία, -logia) is the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting (in contrast with climatology). Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the eighteenth century. The nineteenth century saw breakthroughs occur after observing networks developed across several countries. Breakthroughs in weather forecasting were achieved in the latter half of the twentieth century, after the development of the computer.

Meteorological phenomena are observable weather events which illuminate and are explained by the science of meteorology. Those events are bound by the variables that exist in Earth's atmosphere. They are temperature, air pressure, water vapor, and the gradients and interactions of each variable, and how they change in time. The majority of Earth's observed weather is located in the troposphere. Different spatial scales are studied to determine how systems on local, region, and global levels impact weather and climatology. Meteorology, climatology, atmospheric physics, and atmospheric chemistry are sub-disciplines of the atmospheric sciences. Meteorology and hydrology compose the interdisciplinary field of hydrometeorology. Interactions between Earth's atmosphere and the oceans are part of coupled ocean-atmosphere studies. Meteorology has application in many diverse fields such as the military, energy production, transport, agriculture and construction.

Human

A human is a member of a species of bipedal primates in the family Hominidae (taxonomically Homo sapiens—Latin: "wise man" or "knowing man").DNA and fossil evidence indicates that modern humans originated in east Africa about 200,000 years ago. When compared to other animals and primates, humans have a highly developed brain, capable of abstract reasoning, language, introspection and problem solving. This mental capability, combined with an erect body carriage that frees the forelimbs (arms) for manipulating objects, has allowed humans to make far greater use of tools than any other species. Humans are distributed worldwide, with significant populations inhabiting most land areas of Earth. The human population on Earth is greater than 6.7 billion, as of February 2009, which is estimated to be roughly 5% of the total that have ever lived.Like most higher primates, humans are social by nature. Humans are particularly adept at utilizing systems of communication—primarily spoken, gestural, and written language—for self-expression, the exchange of ideas, and organization. Humans create complex social structures composed of many cooperating and competing groups, from families to nations. Social interactions between humans have established an extremely wide variety of traditions, rituals, ethics, values, social norms, and laws, which together form the basis of human society. Humans are distinctive as a species on the Earth by having a perception of beauty and aesthetics at least to a point which results in a material culture. This, when combined with the desire for self-expression and a proportionally large brain-size, has led to innovations such as art, written language, music and science.

Humans seek to understand and influence the environment around them, trying to explain and manipulate natural phenomena through philosophy, art, science, mythology, and religion. This natural curiosity has led to the development of advanced tools and skills. Although humans are not the only species to use tools, they are unique in building fires, cooking their food, and clothing themselves; as well as using other advanced technologies. Humans pass down their skills and knowledge to the next generations and so are regarded as dependent upon culture.

Global warming

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the last century.The Intergovernmental Panel on Climate Change (IPCC) concludes that increasing greenhouse gas concentrations resulting from human activity such as fossil fuel burning and deforestation are responsible for most of the observed temperature increase since the middle of the 20th century. The IPCC also concludes that natural phenomena such as solar variation and volcanoes produced most of the warming from pre-industrial times to 1950 and had a small cooling effect afterward. These basic conclusions have been endorsed by more than 45 scientific societies and academies of science, including all of the national academies of science of the major industrialized countries.

Climate model projections summarized in the latest IPCC report indicate that the global surface temperature will probably rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the twenty-first century. The uncertainty in this estimate arises from the use of models with differing sensitivity to greenhouse gas concentrations and the use of differing estimates of future greenhouse gas emissions. Some other uncertainties include how warming and related changes will vary from region to region around the globe. Most studies focus on the period up to the year 2100. However, warming is expected to continue beyond 2100 even if emissions stop, because of the large heat capacity of the oceans and the long lifetime of carbon dioxide in the atmosphere.

Increasing global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, probably including expansion of subtropical deserts. The continuing retreat of glaciers, permafrost and sea ice is expected, with the Arctic region being particularly affected. Other likely effects include shrinkage of the Amazon rainforest and Boreal forests, increases in the intensity of extreme weather events, species extinctions, and changes in agricultural yields.

Political and public debate continues regarding what actions (if any) to take in response to global warming. The available options are mitigation to reduce further emissions; adaptation to reduce the damage caused by warming; and, more speculatively, geoengineering to reverse global warming. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gas emissions.

Histology

Histology (compound of the Greek words: στός "tissue", and -λογία -logia) is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining a thin slice (section) of tissue under a light microscope or electron microscope. The ability to visualize or differentially identify microscopic structures is frequently enhanced through the use of histological stains. Histology is an essential tool of biology and medicine.

Histopathology, the microscopic study of diseased tissue, is an important tool in anatomical pathology, since accurate diagnosis of cancer and other diseases usually requires histopathological examination of samples. Trained medical doctors, frequently board-certified as Pathologists, are the personnel who perform histopathological examination and provide diagnostic information based on their observations.

The trained scientists who perform the preparation of histological sections are histotechnicians, histology technicians (HT), histology technologists (HTL), medical scientists, medical laboratory technicians, or biomedical scientists. Their field of study is called histotechnology.

Exact differential equation

Embryology

Embryology (from Greek μβρυον, embryon, "unborn, embryo"; and -λογία, -logia) is the study of the development of an embryo. An embryo is defined as any organism in an early stage well before birth or hatching, or in plants, before germination occurs.
Morula, 8 cell stage
1 - morula, 2 - blastula
1 - blastula, 2 - gastrula with blastopore; orange - ectoderm, red - endoderm.
Embryology refers to the study of the development immediately after conception, and therefore the fertilized egg cell (zygote) and its differentiation into tissues and organs during the first 8 weeks, after 8 weeks the embryo becomes a fetus. After cleavage, the dividing cells, or morula, becomes a hollow ball, or blastula, which develops a hole or pore at one end.
In bilateral animals, the blastula develops in one of two ways that divides the whole animal kingdom into two halves (see: Embryological origins of the mouth and anus). If in the blastula the first pore (blastopore) becomes the mouth of the animal, it is a protostome; if the first pore becomes the anus then it is a deuterostome. The protostomes include most invertebrate animals, such as insects, worms and molluscs, while the deuterostomes includes more advanced animals including the vertebrates. In due course, the blastula changes into a more differentiated structure called the gastrula.
The gastrula with its blastopore soon develops three distinct layers of cells (the germ layers) from which all the bodily organs and tissues then develop:
The innermost layer, or endoderm, gives rise to the digestive organs, lungs and bladder.
The middle layer, or mesoderm, gives rise to the muscles, skeleton and blood system.
The outer layer of cells, or ectoderm, gives rise to the nervous system and skin.
In humans, the term embryo refers to the ball of dividing cells from the moment the zygote implants itself in the uterus wall until the end of the eighth week after conception. Beyond the eighth week, the developing human is then called a fetus. Embryos in many species often appear similar to one another in early developmental stages. The reason for this similarity is because species have a shared evolutionary history. These similarities among species are called homologous structures, which are structures that have the same or similar function and mechanism having evolved from a common ancestor.

DNA

Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. The main role of DNA molecules is the long-term storage of information. DNA is often compared to a set of blueprints or a recipe, or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information.
Chemically, DNA consists of two long polymers of simple units called nucleotides, with backbones made of sugars and phosphate groups joined by ester bonds. These two strands run in opposite directions to each other and are therefore anti-parallel. Attached to each sugar is one of four types of molecules called bases. It is the sequence of these four bases along the backbone that encodes information. This information is read using the genetic code, which specifies the sequence of the amino acids within proteins. The code is read by copying stretches of DNA into the related nucleic acid RNA, in a process called transcription.
Within cells, DNA is organized into X-shaped structures called chromosomes. These chromosomes are duplicated before cells divide, in a process called DNA replication. Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in the mitochondria (animals and plants) and chloroplasts (plants only)[1]. Prokaryotes (bacteria and archaea) however, store their DNA in the cell's cytoplasm. Within the chromosomes, chromatin proteins such as histones compact and organize DNA. These compact structures guide the interactions between DNA and other proteins, helping control which parts of the DNA are transcribed.

Diamond

In mineralogy, diamond (from the ancient Greek adámas, meaning "proper" or "unalterable") is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face centered cubic crystal structure called a diamond lattice. Diamond is the second most stable form of carbon after graphite; however, the conversion rate from diamond to graphite is negligible at ambient conditions. Diamond is specifically renowned as a material with superlative physical qualities, most of which originate from the strong covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material synthesized so far. Those properties determine the major industrial application of diamond in cutting and polishing tools.
Diamond has remarkable optical characteristics. Because of its extremely rigid lattice, it can be contaminated by only few types of impurities, such as boron and nitrogen. Combined with the wide transparency (corresponding to the wide band gap of 5.5 eV), this results in clear, colorless appearance of most natural diamonds. Small amounts of defects or impurities (about one part per million) color diamond blue (boron), yellow (nitrogen), brown (lattice defects), green, purple, pink, orange or red. Diamond also has relatively high optical dispersion, that is ability to disperse light of different colors, which results in its characteristic luster. Excellent optical and mechanical properties, combined with efficient marketing, make diamond the most popular gemstone.
Most natural diamonds are formed at high-pressure high-temperature conditions existing at depths of 140 km to 190 km in the Earth mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years, which respectively corresponds to roughly 25% and 75% of the age of the Earth. Diamonds are brought close to the Earth surface through deep volcanic eruptions by a magma, which cools into igneous rocks known as kimberlites and lamproites. Diamonds can also be produced synthetically in a high-pressure high-temperature process which approximately simulates the conditions in the Earth mantle. An alternative, and completely different growth technique is chemical vapor deposition. Several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have been specially developed to distinguish natural and synthetic diamonds and diamond simulants.

Currucy

In monetary economics Currency can refer either to a particular currency, for example British Pounds or United States Dollars, or, to the coins and banknotes of a particular currency, which comprise the monetary base of a nation’s money supply. The other part of a nation’s money supply consists of money deposited in banks (sometimes called deposit money), ownership of which can be transferred by means of checks (cheques in the United Kingdom and Australia) or other forms of money transfer such as credit and debit cards. Deposit money and currency are ‘money’ in the sense that both are acceptable as a means of exchange, but money need not necessarily be ‘currency’.
Historically, money in the form of currency has predominated. Usually (gold or silver) coins of intrinsic value commensurate with the monetary unit (commodity money), have been the norm. By contrast, modern currency, as fiat money, is intrinsically worthless. The prevalence of one type of currency over another in commodity money systems has arisen, usually when a government designates through decrees, that only particular monetary units shall be accepted in payment for taxes.

Atmosphere

An atmosphere (from Greek ατμός - atmos, 'vapor' + σφαίρα - sphaira, 'sphere') is a layer of gases that may surround a material body of sufficient mass, by the gravity of the body, and are retained for a longer duration if gravity is high and the atmosphere's temperature is low. Some planets consist mainly of various gases, but only their outer layer is their atmosphere (see gas giants).
The term stellar atmosphere describes the outer region of a star, and typically includes the portion starting from the opaque photosphere outwards. Relatively low-temperature stars may form compound molecules in their outer atmosphere. Earth's atmosphere, which contains oxygen used by most organisms for respiration and carbon dioxide used by plants, algae and cyanobacteria for photosynthesis, also protects living organisms from genetic damage by solar ultraviolet radiation. Its current composition is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms

Astronomy

Astronomy (from the Greek words astron (στρον), "star", and nomos (νόμος), "law") is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earth's atmosphere (such as the cosmic background radiation). It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe.
Astronomy is one of the oldest sciences. Astronomers of early civilizations performed methodical observations of the night sky, and astronomical artifacts have been found from much earlier periods. However, the invention of the telescope was required before astronomy was able to develop into a modern science. Historically, astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, the making of calendars, and even astrology, but professional astronomy is nowadays often considered to be synonymous with astrophysics. Since the 20th century, the field of professional astronomy split into observational and theoretical branches. Observational astronomy is focused on acquiring and analyzing data, mainly using basic principles of physics. Theoretical astronomy is oriented towards 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 the observational results, and observations being used to confirm theoretical results.
Amateur astronomers have contributed to many important astronomical discoveries, and astronomy is one of the few sciences where amateurs can still play an active role, especially in the discovery and observation of transient phenomena.
Old or even ancient astronomy is not to 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 and a part of their methods (namely, the use of ephemerides), they are distinct.
2009 has been declared by the UN to be the International Year of Astronomy 2009 (IYA2009). The focus is on enhancing the public’s understanding and engagement with astronomy.

Astrology

Astrology (from Greek στρον, astron, "constellation, star"; and -λογία, -logia, "the study of") is a group of systems, traditions, and beliefs which hold that the relative positions of celestial bodies and related details can provide information about personality, human affairs, and other terrestrial matters. A practitioner of astrology is called an astrologer or astrologist.
Numerous traditions and applications employing astrological concepts have arisen since its earliest recorded beginnings in the 3rd millennium BC. Astrology has played an important role in the shaping of culture, early astronomy, the Vedas,the Bible, and various disciplines throughout history. In fact, astrology and astronomy were often indistinguishable before the modern era, with the desire for predictive and divinatory knowledge one of the primary motivating factors for astronomical observation. Astronomy began to diverge from astrology after a period of gradual separation from the Renaissance up until the 18th century. Eventually, astronomy distinguished itself as the scientific study of astronomical objects and phenomena without regard to the astrological understandings of these phenomena.
Astrologers believe that the movements and positions of celestial bodies either directly influence life on Earth or correspond to events experienced on a human scale. Modern astrologers define astrology as a symbolic language,an art form, or a form of divination.Despite differences in definitions, a common assumption of astrology is that celestial placements can aid in the interpretation of past and present events and in the prediction of the future.
Scientists consider astrology a pseudoscience or superstition. In one poll, 31% of Americans expressed a belief in astrology and, according to another study, 39% considered it scientific.

Archaeology

Archaeology, archeology, or archæology (from Greek ρχαιολογία, archaiologia – ρχαος, archaīos, "primal, ancient, old"; and -λογία, -logia) is the science that studies human cultures through the recovery, documentation, analysis, and interpretation of material remains and environmental data, including architecture, artifacts, features, biofacts, and landscapes. Because archaeology's aim is to understand humankind, it is a humanistic endeavor. Due to its analysis of human cultures, it is a subset of anthropology, which contains: physical anthropology, cultural anthropology, archaeology, and linguistic anthropology. There is debate as to what archaeology's goals are. Some goals include the documentation and explanation of the origins and development of human cultures, understanding culture history, chronicling cultural evolution, and studying human behavior and ecology, for both prehistoric and historic societies[citation needed].
Archaeologists are also concerned with the study of methods used in the discipline, and the theoretical and philosophical underpinnings underlying the questions archaeologists ask of the past. The tasks of surveying areas in order to find new sites, excavating sites in order to recover cultural remains, classification, analysis, and preservation are all important phases of the archaeological process. Given the broad scope of the discipline, there is cross-disciplinary research in archaeology. It draws upon anthropology, history, art history, classics, ethnology, geography, geology, linguistics, physics, information sciences, chemistry, statistics, paleoecology, paleontology, paleozoology, paleoethnobotany, and paleobotany.

Anatomy

Anatomy (from the Greek νατομία anatomia, from νατέμνειν ana: separate, apart from, and temnein, to cut up, cut open) is a branch of biology and Medicine which studies primarily the internal structure and design of the structure of living things. It is a general term that includes human anatomy, animal anatomy (zootomy) and plant anatomy (phytotomy). Anatomy is divided into various sub specialties in some of its facets anatomy is closely related to Embryology, Histology, comparative anatomy and comparative embryology,through common roots in evolution.
Anatomy is subdivided into gross anatomy (or macroscopic anatomy) and microscopic anatomy. Gross anatomy (also called topographical anatomy, regional anatomy, or anthropotomy) is the study of anatomical structures that can be seen by unaided vision with the naked eye.Microscopic anatomy is the study of minute anatomical structures assisted with microscopes, which includes histology (the study of the organization of tissues), and cytology (the study of cells).
The history of anatomy has been characterized, over time, by a continually developing understanding of the functions of organs and structures in the body including the clinical understanding of how damage to these structures effects other functions in the body. Methods have also advanced dramatically, advancing from examination of animals through dissection of cadavers (dead human bodies) to technologically complex techniques developed in the 20th century including X-ray technology, Sonogram and MRI technology.
Anatomy should not be confused with anatomical pathology (also called morbid anatomy or histopathology), which is the study of the gross and microscopic appearances of diseased organs.

Aircraft

An aircraft is a vehicle which is able to fly by being supported by the air, or in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift (as with balloons, blimps and dirigibles) or by using the dynamic lift of an airfoil (as with vehicles that plane the air with wings in a straight manner, such as airplanes and gliders, or vehicles that generate lift with wings in a rotary manner, such as helicopters or gyrocopters).
Objects which fly, but are not supported by the air, such as most rockets and missiles, are not considered aircraft. These types of vehicles use rocket thrust instead of lift as the primary means of overcoming the force of gravity. Other objects which fly by using aerodynamic lift, such as kites and Frisbees, can only be considered aircraft if they are used as vehicles.[citation needed] Ballistic flying objects such as arrows, bullets and artillery are not aircraft, because they do not use the air as their means for countering the force of gravity. Parachutes are not usually considered to be aircraft (although they may be) because they have a lift-to-drag ratio well below one, and thus fly extremely poorly. However, parasails and paragliders possess a much high lift-to-drag ratio and are nearly always considered aircraft. For an even more specialized case a rocket with wings such as the X-1, X-15 or the EZ-Rocket does typically function as an aircraft when it is flying in its rocket mode using aerodynamic lift, but would not if flown as a spacecraft outside of the atmosphere, and where it is therefore not supported by the air. So it is possible for the same vehicle to either count or not count as an aircraft depending upon its usage.
The human activity which surrounds aircraft is called aviation. Manned aircraft are flown by an onboard pilot. Unmanned vehicles are often called drones, remotely piloted vehicles (RPV) or unmanned aerial vehicles (UAV).

Age of earth

Modern geologists and geophysicists consider the age of the Earth to be around 4.54 billion years (4.54 × 109 years ± 1%). This age has been determined by radiometric age dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and lunar samples.
Following the scientific revolution and the development of radiometric age dating, measurements of lead in uranium-rich minerals showed that some were in excess of a billion years old.The oldest such minerals analysed to date – small crystals of zircon from the Jack Hills of Western Australia – are at least 4.404 billion years old.Comparing the mass and luminosity of the Sun to the multitudes of other stars, it appears that the solar system cannot be much older than those rocks. Ca-Al-rich inclusions (inclusions rich in calcium and aluminium) – the oldest known solid constituents within meteorites that are formed within the solar system – are 4.567 billion years old,giving an age for the solar system and an upper limit for the age of Earth. It is hypothesised that the accretion of Earth began soon after the formation of the Ca-Al-rich inclusions and the meteorites. Because the exact accretion time of Earth is not yet known, and the predictions from different accretion models range from a few millions up to about 100 million years, the exact age of Earth is difficult to determine. It is also difficult to determine the exact age of the oldest rocks on Earth, exposed at the surface, as they are aggregates of minerals of possibly different ages. The Acasta Gneiss of Northern Canada may be the oldest known exposed crustal rock.

IMPROPER INTEGRAL

In calculus, an improper integral is the limit of a definite integral as an endpoint of the interval of integration approaches either a specified real number or ∞ or −∞ or, in some cases, as both endpoints approach limits.
Specifically, an improper integral is a limit of the form
or of the form
in which one takes a limit in one or the other (or sometimes both) endpoints (Apostol 1967, §10.23). Improper integrals may also occur at an interior point of the domain of integration, or at multiple such points.
It is often necessary to use improper integrals in order to compute a value for integrals which may not exist in the conventional sense (as a Riemann integral, for instance) because of a singularity in the function, or an infinite endpoint of the domain of integration.

FUNCTION

The mathematical concept of a function expresses dependence between two quantities, one of which is known and the other which is produced. A function associates a single output to each input element drawn from a fixed set, such as the real numbers (), although different inputs may have the same output.
There are many ways to give a function: by a formula, by a plot or graph, by an algorithm that computes it, or by a description of its properties. Sometimes, a function is described through its relationship to other functions (see, for example, inverse function). In applied disciplines, functions are frequently specified by their tables of values or by a formula. Not all types of description can be given for every possible function, and one must make a firm distinction between the function itself and multiple ways of presenting or visualizing it.
One idea of enormous importance in all of mathematics is composition of functions: if z is a function of y and y is a function of x, then z is a function of x. We may describe it informally by saying that the composite function is obtained by using the output of the first function as the input of the second one. This feature of functions distinguishes them from other mathematical constructs, such as numbers or figures, and provides the theory of functions with its most powerful structure.

INTEGRATION

Integration is an important concept in mathematics which, together with differentiation, forms one of the main operations in calculus. Given a function ƒ of a real variable x and an interval [a, b] of the real line, the definite integral
is defined informally to be the net signed area of the region in the xy-plane bounded by the graph of ƒ, the x-axis, and the vertical lines x = a and x = b.
The term "integral" may also refer to the notion of antiderivative, a function F whose derivative is the given function ƒ. In this case it is called an indefinite integral, while the integrals discussed in this article are termed definite integrals. Some authors maintain a distinction between antiderivatives and indefinite integrals.
The principles of integration were formulated independently by Isaac Newton and Gottfried Leibniz in the late seventeenth century. Through the fundamental theorem of calculus, which they independently developed, integration is connected with differentiation: if ƒ is a continuous real-valued function defined on a closed interval [a, b], then, once an antiderivative F of ƒ is known, the definite integral of ƒ over that interval is given by
Integrals and derivatives became the basic tools of calculus, with numerous applications in science and engineering. A rigorous mathematical definition of the integral was given by Bernhard Riemann. It is based on a limiting procedure which approximates the area of a curvilinear region by breaking the region into thin vertical slabs. Beginning in the nineteenth century, more sophisticated notions of integral began to appear, where the type of the function as well as the domain over which the integration is performed has been generalised. A line integral is defined for functions of two or three variables, and the interval of integration [a, b] is replaced by a certain curve connecting two points on the plane or in the space. In a surface integral, the curve is replaced by a piece of a surface in the three-dimensional space. Integrals of differential forms play a fundamental role in modern differential geometry. These generalizations of integral first arose from the needs of physics, and they play an important role in the formulation of many physical laws, notably those of electrodynamics. There are many modern concepts of integration. The most common notion of integration is based on the abstract mathematical theory known as Lebesgue integration, developed by Henri Lebesgue