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Ancient American Engineering
Ancient American Engineering refers to early American applied scientific and mathematical knowledge used to design and build structures, machines, devices, systems and material prior to the arrival and influence of Western and Eastern Civilizations. This knowledge belonged to the Aztecs, Incas, Mayans, and Anasazi, and covered two continents. History An analysis of Ancient American Engineering works shows that the engineers adhered strictly to two important principles: the efficient use of the resources available and the effectiveness of a project design. Of the resources available then, the tools were quite rudimentary: none of iron, some of copper and other metals, but mostly of wood and stone. Nor was there any sophisticated means of transportation - only animals for carrying cargo and, even these, only in certain regions. The manual labor, abundant when mobilized by a strong socio-political organization, produced the bulk of the work. Another abundant resource then, compared to n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with their associated islands, the Americas cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon, St. Lawrence River–Great Lakes basin, Mississippi, and La Plata. Since the Americas extend from north to south, the climate and ecology vary widely, from the arctic tundra of Northern Canada, Greenland, and Alaska, to the tropical rain forests in Central America and South America. Humans first settled the Americas from Asia between 42,000 and 17,000 years ago. A second migration of Na-Dene speakers followed later ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Town
A town is a human settlement. Towns are generally larger than villages and smaller than cities, though the criteria to distinguish between them vary considerably in different parts of the world. Origin and use The word "town" shares an origin with the German word , the Dutch word , and the Old Norse . The original Proto-Germanic word, *''tūnan'', is thought to be an early borrowing from Proto-Celtic *''dūnom'' (cf. Old Irish , Welsh ). The original sense of the word in both Germanic and Celtic was that of a fortress or an enclosure. Cognates of ''town'' in many modern Germanic languages designate a fence or a hedge. In English and Dutch, the meaning of the word took on the sense of the space which these fences enclosed, and through which a track must run. In England, a town was a small community that could not afford or was not allowed to build walls or other larger fortifications, and built a palisade or stockade instead. In the Netherlands, this space was a garden, mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canal
Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow under atmospheric pressure, and can be thought of as artificial rivers. In most cases, a canal has a series of dams and locks that create reservoirs of low speed current flow. These reservoirs are referred to as ''slack water levels'', often just called ''levels''. A canal can be called a ''navigation canal'' when it parallels a natural river and shares part of the latter's discharges and drainage basin, and leverages its resources by building dams and locks to increase and lengthen its stretches of slack water levels while staying in its valley. A canal can cut across a drainage divide atop a ridge, generally requiring an external water source above the highest elevation. The best-known example of such a canal is the Panama Canal. Many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bridge
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually something that is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, and the material used to make it, and the funds available to build it. The earliest bridges were likely made with fallen trees and stepping stones. The Neolithic people built boardwalk bridges across marshland. The Arkadiko Bridge (dating from the 13th century BC, in the Peloponnese) is one of the oldest arch bridges still in existence and use. Etymology The '' Oxford English Dictionary'' traces the origin of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Causeway
A causeway is a track, road or railway on the upper point of an embankment across "a low, or wet place, or piece of water". It can be constructed of earth, masonry, wood, or concrete. One of the earliest known wooden causeways is the Sweet Track in the Somerset Levels, England, which dates from the Neolithic age. Timber causeways may also be described as both boardwalks and bridges. Etymology When first used, the word ''causeway'' appeared in a form such as "causey way" making clear its derivation from the earlier form "causey". This word seems to have come from the same source by two different routes. It derives ultimately, from the Latin for heel, ''calx'', and most likely comes from the trampling technique to consolidate earthworks. Originally, the construction of a causeway utilised earth that had been trodden upon to compact and harden it as much as possible, one layer at a time, often by enslaved bodies or flocks of sheep. Today, this work is done by machines. The s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenochtitlan
, ; es, Tenochtitlan also known as Mexico-Tenochtitlan, ; es, México-Tenochtitlan was a large Mexican in what is now the historic center of Mexico City. The exact date of the founding of the city is unclear. The date 13 March 1325 was chosen in 1925 to celebrate the 600th anniversary of the city. The city was built on an island in what was then Lake Texcoco in the Valley of Mexico. The city was the capital of the expanding Aztec Empire in the 15th century until it was captured by the Spanish in 1521. At its peak, it was the largest city in the pre-Columbian Americas. It subsequently became a '' cabecera'' of the Viceroyalty of New Spain. Today, the ruins of are in the historic center of the Mexican capital. The World Heritage Site of contains what remains of the geography (water, boats, floating gardens) of the Mexica capital. was one of two Mexica (city-states or polities) on the island, the other being . The city is located in modern-day Mexico City. Etymolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
City-state
A city-state is an independent sovereign city which serves as the center of political, economic, and cultural life over its contiguous territory. They have existed in many parts of the world since the dawn of history, including cities such as Rome, Athens, Sparta, Carthage, and the Italian city-states during the Middle Ages and Renaissance, such as Florence, Venice, Genoa and Milan. With the rise of nation states worldwide, only a few modern sovereign city-states exist, with some disagreement as to which qualify; Monaco, Singapore and Vatican City are most commonly accepted as such. Singapore is the clearest example, with full self-governance, its own currency, a robust military and a population of 5.5 million. Several non-sovereign cities enjoy a high degree of autonomy and are sometimes considered city-states. Hong Kong, Macau, and members of the United Arab Emirates—most notably Dubai and Abu Dhabi—are often cited as such. Historical background Ancient and medi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Egyptian astronomy, Egyptians, Chinese astronomy, Chinese, Maya civilization, Maya, and many anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is called a ''geometer''. Until the 19th century, geometry was almost exclusively devoted to Euclidean geometry, which includes the notions of point, line, plane, distance, angle, surface, and curve, as fundamental concepts. During the 19th century several discoveries enlarged dramatically the scope of geometry. One of the oldest such discoveries is Carl Friedrich Gauss' ("remarkable theorem") that asserts roughly that the Gaussian curvature of a surface is independent from any specific embedding in a Euclidean space. This implies that surfaces can be studied ''intrinsically'', that is, as stand-alone spaces, and has been expanded into the theory of manifolds and Riemannian geometry. Later in the 19th century, it appeared that geometries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting points of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stars
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make them appear as fixed points of light. The most prominent stars have been categorised into constellations and asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its total mass is the main factor determining its evolution and eventual fate. A star shines for most of its active life du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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