Wednesday, August 31, 2011

BIGBANGTHEORY

The Big Bang Model is a broadly accepted theory for the origin and evolution of our universe. It postulates that 12 to 14 billion years ago, the portion of the universe we can see today was only a few millimeters across. It has since expanded from this hot dense state into the vast and much cooler cosmos we currently inhabit. We can see remnants of this hot dense matter as the now very cold cosmic microwave background radiation which still pervades the universe and is visible to microwave detectors as a uniform glow across the entire sky.

Tuesday, August 30, 2011

civilengineering

Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like bridges, roads, canals, dams, and buildings.[1][2][3] Civil engineering is the oldest engineering discipline after military engineering,[4] and it was defined to distinguish non-military engineering from military engineering.[5] It is traditionally broken into several sub-disciplines including environmental engineering, geotechnical engineering, structural engineering, transportation engineering, municipal or urban engineering, water resources engineering, materials engineering, coastal engineering,[4] surveying, and construction engineering.[6] Civil engineering takes place on all levels: in the public sector from municipal through to national governments, and in the private sector from individual homeowners through to international companies.Engineering has been an aspect of life since the beginnings of human existence. The earliest practices of Civil engineering may have commenced between 4000 and 2000 BC in Ancient Egypt and Mesopotamia (Ancient Iraq) when humans started to abandon a nomadic existence, thus causing a need for the construction of shelter. During this time, transportation became increasingly important leading to the development of the wheel and sailing.

Until modern times there was no clear distinction between civil engineering and architecture, and the term engineer and architect were mainly geographical variations referring to the same person, often used interchangeably.[7] The construction of Pyramids in Egypt (circa 2700-2500 BC) might be considered the first instances of large structure constructions. Other ancient historic civil engineering constructions include the Qanat water management system (the oldest older than 3000 years and longer than 71 km[8],) the Parthenon by Iktinos in Ancient Greece (447-438 BC), the Appian Way by Roman engineers (c. 312 BC), the Great Wall of China by General Meng T'ien under orders from Ch'in Emperor Shih Huang Ti (c. 220 BC)[6] and the stupas constructed in ancient Sri Lanka like the Jetavanaramaya and the extensive irrigation works in Anuradhapura. The Romans developed civil structures throughout their empire, including especially aqueducts, insulae, harbours, bridges, dams and roads.
The Archimedes screw was operated by hand and could raise water efficiently.

In the 18th century, the term civil engineering was coined to incorporate all things civilian as opposed to military engineering.[5] The first self-proclaimed civil engineer was John Smeaton who constructed the Eddystone Lighthouse.[4][6] In 1771 Smeaton and some of his colleagues formed the Smeatonian Society of Civil Engineers, a group of leaders of the profession who met informally over dinner. Though there was evidence of some technical meetings, it was little more than a social society.

In 1818 the Institution of Civil Engineers was founded in London, and in 1820 the eminent engineer Thomas Telford became its first president. The institution received a Royal Charter in 1828, formally recognising civil engineering as a profession. Its charter defined civil engineering as:

the art of directing the great sources of power in nature for the use and convenience of man, as the means of production and of traffic in states, both for external and internal trade, as applied in the construction of roads, bridges, aqueducts, canals, river navigation and docks for internal intercourse and exchange, and in the construction of ports, harbours, moles, breakwaters and lighthouses, and in the art of navigation by artificial power for the purposes of commerce, and in the construction and application of machinery, and in the drainage of cities and towns.[9]

The first private college to teach Civil Engineering in the United States was Norwich University founded in 1819 by Captain Alden Partridge.[10] The first degree in Civil Engineering in the United States was awarded by Rensselaer Polytechnic Institute in 1835.[11] The first such degree to be awarded to a woman was granted by Cornell University to Nora Stanton Blatch in 1905.[12]

ElectronicRobert


A robot is a mechanical intelligent agent which can perform tasks on its own, or with guidance. In practice a robot is usually an electro-mechanical machine which is guided by computer and electronic programming. Robots can be autonomous or semi-autonomous and come in those two basic types: those which are used for research into human-like systems, such as ASIMO and TOPIO, as well as those into more defined and specific roles, such as Nano robots and Swarm robots; and helper robots which are used to make or move things or perform menial or dangerous tasks, such as Industrial robots or mobile or servicing robots. Another common characteristic is that, by its appearance or movements, a robot often conveys a sense that it has intent or agency of its own.

When societies first began developing, nearly all production and effort was the result of human labour, as well as with the aid of semi- and fully domesticated animals. As mechanical means of performing functions were discovered, and mechanics and complex mechanisms were developed, the need for human labour was reduced. Machinery was initially used for repetitive functions, such as lifting water and grinding grain. With technological advances more complex machines were slowly developed, such as those invented by Hero of Alexandria (in Egypt) in the 1st century AD, and the first half of the second millennium AD, such as the Automata of Al-Jazari in the 12th century AD (in medieval Iraq). They were not widely adopted as human labour, particularly slave labour, was still inexpensive compared to the capital-intensive machines. Men such as Leonardo Da Vinci in 1495 through to Jacques de Vaucanson in 1739, as well as rediscovering the Greek engineering methods, have made plans for and built automata and robots leading to books of designs such as the Japanese Karakuri zui (Illustrated Machinery) in 1796. As mechanical techniques developed through the Industrial age we find more practical applications such as Nikola Tesla in 1898, who designed a radio-controlled torpedo, and the Westinghouse Electric Corporation creation of Televox in 1926. From here we also find a more android development as designers tried to mimic more human-like features including designs such as those of biologist Makoto Nishimura in 1929 and his creation Gakutensoku, which cried and changed its facial expressions, and the more crude Elektro from Westinghouse in 1938.

Electronics then became the driving force of development instead of mechanics, with the advent of the first electronic autonomous robots created by William Grey Walter in Bristol, England, in 1948. The first digital and programmable robot was invented by George Devol in 1954 and was ultimately called the Unimate. Devol sold the first Unimate to General Motors in 1960 where it was used to lift pieces of hot metal from die casting machines in a plant in Trenton, New Jersey. Since then we have seen robots finally reach a more true assimilation of all technologies to produce robots such as ASIMO which can walk and move like a human. Robots have replaced slaves in the assistance of performing those repetitive and dangerous tasks which humans prefer not to do, or are unable to do due to size limitations, or even those such as in outer space or at the bottom of the sea where humans could not survive the extreme environments.

Man has developed an awareness of the problems associated with autonomous robots and how they may act in society. Fear of robot behaviour, such as Shelley's Frankenstein and the EATR, drive current practice in establishing what autonomy a robot should and should not be capable of. Thinking has developed through discussion of robot control and artificial intelligence (AI) and how its application should benefit society, such as those based around Asimov's three laws. Practicality still drives development forwards and robots are used in an increasingly wide variety of tasks such as vacuuming floors, mowing lawns, cleaning drains, investigating other planets, building cars, in entertainment and in warfare.