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Airport ( 10375 views )
Airport 
Licensed under Creative Commons Attribution-Share Alike 3.0 (CellarDoor85 (Robert Aehnelt).).
An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports often have facilities to store and maintain aircraft, and a control tower. An airport consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surface such as a runway for a plane to take off or a helipad, and often includes adjacent utility buildings such as control towers, hangars and terminals. Larger airports may have airport aprons, taxiway bridges, air traffic control centres, passenger facilities such as restaurants and lounges, and emergency services. In some countries, the US in particular, they also typically have one or more fixed-base operators, serving general aviation.
An airport solely serving helicopters is called a heliport. An airport for use by seaplanes and amphibious aircraft is called a seaplane base. Such a base typically includes a stretch of open water for takeoffs and landings, and seaplane docks for tying-up.
An international airport has additional facilities for customs and passport control as well as incorporating all of the aforementioned elements. Such airports rank among the most complex and largest of all built typologies with 15 of the top 50 buildings by floor area being airport terminals.
Airport Seating ( 7817 views )
Airport Seating 
Licensed under Creative Commons Attribution-Share Alike 2.0 (Jonathan Billinger).
An airport chair or airport seating is seating within an airport.
Airport terminals designed by major architects such as Renzo Piano (Kansai International Airport) or Richard Rogers (London Heathrow Terminal 5) require high quality seating to match the general quality of their interiors.
Fire safety is a significant consideration at airports. Regulations now govern the contents of airport terminals and this affects the choice of materials used for the seating. Werner Sobek designed the airport chair Expression using only aluminium in a simple form.
Recent firms and designers involved in the highly lucrative and competitive business include Porsche, Vitra, Sir Norman Foster, and Alberto Meda.
Business travellers commonly wish to use laptop computers while waiting and so seating for them may incorporate a charging point and a form of desk.
Robert Sommer studied the design of airport seating and concluded that the arrangement of chairs in rigid lines bolted to the floor was deliberately sociofugal — discouraging social interaction such as conversation and encouraging the sitters to go to commercial locations such as shops and cafes. The provision of arms on the chairs increased the usage of the chairs, as compared with bench seats without arms. Strangers are more comfortable sitting adjacent each other if there is an arm to mark their personal space. The parallel orientation of the modular seat units also minimises face-to-face contact and this is less threatening for strangers.
Airship ( 15662 views )
Airship 
Licensed under Creative Commons Attribution-Share Alike 3.0 (AngMoKio).
An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from large gasbags filled with a lifting gas that is less dense than the surrounding air.
In early dirigibles, the lifting gas used was hydrogen, due to its high lifting capacity and ready availability. Helium gas has almost the same lifting capacity and is not flammable, unlike hydrogen, but is rare and relatively expensive. Significant amounts were first discovered in the United States and for a while helium was only used for airships in that country. Most airships built since the 1960s have used helium, though some have used hot air.The envelope of an airship may form a single gasbag, or may contain a number of internal gas-filled cells. An airship also has engines, crew, and optionally also payload accommodation, typically housed in one or more "gondolas" suspended below the envelope.
The main types of airship are non-rigid, semi-rigid, and rigid. Non-rigid airships, often called "blimps", rely on internal pressure to maintain their shape. Semi-rigid airships maintain the envelope shape by internal pressure, but have some form of supporting structure, such as a fixed keel, attached to it. Rigid airships have an outer structural framework that maintains the shape and carries all structural loads, while the lifting gas is contained in one or more internal gasbags or cells. Rigid airships were first flown by Count Zeppelin and the vast majority of rigid airships built were manufactured by the firm he founded. As a result, rigid airships are often called zeppelins.Airships were the first aircraft capable of controlled powered flight, and were most commonly used before the 1940s; their use decreased over time as their capabilities were surpassed by those of aeroplanes. Their decline was accelerated by a series of high-profile accidents, including the 1930 crash and burning of British R101 in France, the 1933 and 1935 storm-related crashes of the twin airborne aircraft carrier U.S. Navy helium-filled rigids, the USS Akron and USS Macon respectively, and the 1937 burning of the hydrogen-filled Hindenburg. From the 1960s, helium airships have been used in applications where the ability to hover in one place for an extended period outweighs the need for speed and manoeuvrability, such as advertising, tourism, camera platforms, geological surveys, and aerial observation.
Airspeed ( 11541 views )
Airspeed 
Airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are indicated airspeed ("IAS"), calibrated airspeed ("CAS"), equivalent airspeed ("EAS"), true airspeed ("TAS"), and density airspeed.
Indicated airspeed is simply what is read off of an airspeed gauge connected to a pitot static system, calibrated airspeed is indicated airspeed adjusted for pitot system position and installation error, and equivalent airspeed is calibrated airspeed adjusted for compressibility effects. True airspeed is equivalent airspeed adjusted for air density, and is also the speed of the aircraft through the air in which it is flying. Calibrated airspeed is typically within a few knots of indicated airspeed, while equivalent airspeed decreases slightly from CAS as aircraft altitude increases or at high speeds.
With EAS constant, true airspeed increases as aircraft altitude increases. This is because air density decreases with higher altitude, but an aircraft's wing requires the same amount of air particles (i.e., mass of air) flowing around it to produce the same amount of lift for a given AOA; thus, a wing must move faster through thinner air than thicker air to obtain the same amount of lift.
The measurement and indication of airspeed is ordinarily accomplished on board an aircraft by an airspeed indicator ("ASI") connected to a pitot-static system. The pitot-static system comprises one or more pitot probes (or tubes) facing the on-coming air flow to measure pitot pressure (also called stagnation, total or ram pressure) and one or more static ports to measure the static pressure in the air flow. These two pressures are compared by the ASI to give an IAS reading.
AL-6XN ( 8459 views )
AL-6XN
AL-6XN (UNS designation N08367) is a type of weldable stainless steel that consist of an alloy of nickel (24%), chromium (22%) and molybdenum (6.3%) with other trace elements such as nitrogen.
The high nickel and molybdenum contents of the AL-6XN alloy give it good resistance to chloride stress-corrosion cracking. The molybdenum confers resistance to chloride pitting. The nitrogen content serves to further increase pitting resistance and also gives it higher strength than typical 300 series austenitic stainless steels, and thereby often allows it to be used in thinner sections.
This metal is commonly used in lieu of 300 series stainless steels in high temperature and low pH applications in food processing. For example, tomato juice will corrode 316L stainless steel at pasteurization temperatures of 210 °F (100 °C). AL-6XN will better resist this corrosion while still offering the beneficial properties of stainless steel.
Alarm clock ( 11446 views )
Alarm clock 
Licensed under Creative Commons Attribution-Share Alike 3.0 (Sun Ladder).
An alarm clock (or sometimes just an alarm) is a clock that is designed to alert an individual or group of individuals at specified time. The primary function of these clocks is to awaken people from their night's sleep or short naps; they are sometimes used for other reminders as well. Most use sound; some use light or vibration. Some have sensors to identify when a person is in a light stage of sleep, in order to avoid waking someone who is deeply asleep, which causes tiredness, even if the person has had adequate sleep. To stop the sound or light, a button or handle on the clock is pressed; most clocks automatically stop the alarm if left unattended long enough. A classic analog alarm clock has an extra hand or inset dial that is used to specify the time at which to activate the alarm. Alarm clocks are also found on mobile phones and watches.
Traditional mechanical alarm clocks have one or two bells that ring by means of a mainspring that powers a gear to propel a hammer back and forth between the two bells or between the interior sides of a single bell. In some models, the back encasement of the clock itself acts as the bell. In an electric bell-style alarm clock, the bell is rung by an electromagnetic circuit and armature that turns the circuit on and off repeatedly.
Digital alarm clocks can make other noises. Simple battery-powered alarm clocks make a loud buzzing or beeping sound to wake a sleeper, while novelty alarm clocks can speak, laugh, sing, or play sounds from nature.
Some alarm clocks have radios that can be set to start playing at specified times, and are known as clock radios. Some alarm clocks can set multiple alarms, a useful feature for couples who have different waking up schedules. A progressive alarm clock, still new in the market, can have different alarms for different times (see Next-Generation Alarms) and even play music of your choice. Most modern televisions, mobile phones and digital watches have alarm clock functions to turn on or make sounds at a specific time.
ALBA (synchrotron) ( 990 views )
ALBA (synchrotron) 
Licensed under Creative Commons Attribution-Share Alike 3.0 (Mariusmm (talk) 19:02, 25 October 2010 (UTC)).
ALBA (meaning "Sunrise" in Catalan and in Spanish) is a 3rd generation synchrotron radiation facility located in the Barcelona Synchrotron Park in Cerdanyola del Vallès near Barcelona, in Catalonia (Spain). It is constructed and operated by the CELLS (sp: Consorcio para la Construcción, Equipamiento y Explotación del Laboratorio de Luz de Sincrotrón, or Consortium for the Exploitation of the Synchrotron Light Laboratory) consortium, and co-financed by the Spanish central administration and regional Catalan GovernmentAfter nearly ten years of planning and design work by the Spanish scientific community, the project was approved in 2002 by the Spanish and the regional Catalan governments. After scientific workshops and meetings with prospective users, the facility was redesigned in 2004, and in 2006 construction started. The laboratory was officially opened for experiments on 7 beamlines in March 2010.
Albert Einstein ( 33125 views )
Albert Einstein 
Albert Einstein (; German: [ˈalbɛɐ̯t ˈaɪnʃtaɪn]; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist.
Einstein developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics). Einstein's work is also known for its influence on the philosophy of science. Einstein is best known by the general public for his mass–energy equivalence formula E = mc2 (which has been dubbed "the world's most famous equation"). He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the evolution of quantum theory.
Near the beginning of his career, Einstein thought that Newtonian mechanics was no longer enough to reconcile the laws of classical mechanics with the laws of the electromagnetic field. This led him to develop his special theory of relativity during his time at the Swiss Patent Office in Bern (1902–1909), Switzerland. However, he realized that the principle of relativity could also be extended to gravitational fields and—with his subsequent theory of gravitation in 1916—he published a paper on general relativity. He continued to deal with problems of statistical mechanics and quantum theory, which led to his explanations of particle theory and the motion of molecules. He also investigated the thermal properties of light which laid the foundation of the photon theory of light. In 1917, Einstein applied the general theory of relativity to model the large-scale structure of the universe.
Between 1895 and 1914 he lived in Switzerland (except for one year in Prague, 1911–12), where he received his academic diploma from the Swiss Federal Polytechnic in Zürich (later the Eidgenössische Technische Hochschule, ETH) in 1900. He later taught there at the same institute as a professor of theoretical physics between 1912 and 1914 before he left for Berlin. In 1901, after being stateless for more than five years, Einstein acquired Swiss citizenship, which he kept for the rest of his life. In 1905, Einstein was awarded a PhD by the University of Zürich. The same year, his annus mirabilis (miracle year), he published four groundbreaking papers, which were to bring him to the notice of the academic world, at the age of 26.
He was visiting the United States when Adolf Hitler came to power in 1933 and—being Jewish—did not go back to Germany, where he had been a professor at the Berlin Academy of Sciences. He settled in the United States, becoming an American citizen in 1940. On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential development of "extremely powerful bombs of a new type" and recommending that the U.S. begin similar research. This eventually led to what would become the Manhattan Project. Einstein supported defending the Allied forces, but generally denounced the idea of using the newly discovered nuclear fission as a weapon. Later, with the British philosopher Bertrand Russell, Einstein signed the Russell–Einstein Manifesto, which highlighted the danger of nuclear weapons. Einstein was affiliated with the Institute for Advanced Study in Princeton, New Jersey, until his death in 1955.
Einstein published more than 300 scientific papers along with over 150 non-scientific works. Einstein's intellectual achievements and originality have made the word "Einstein" synonymous with "genius".
Alcoa ( 3780 views )
Alcoa
Alcoa Corporation (from aluminum company of America) is an American industrial corporation. It is the world's sixth largest producer of aluminum, with corporate headquarters in Pittsburgh, Pennsylvania. Alcoa conducts operations in 10 countries. Alcoa is a major producer of primary aluminum, fabricated aluminum, and alumina combined, through its active and growing participation in all major aspects of the industry: technology, mining, refining, smelting, fabricating, and recycling.
In May 2007 Alcoa Inc. made a US$27 billion hostile takeover bid for Alcan in an attempt to form the world's largest aluminum producer. The bid was withdrawn when Alcan announced a friendly takeover by Rio Tinto in July 2007.
On November 1, 2016, Alcoa Inc. split into two new entities: Alcoa Corporation, which is engaged in the mining and manufacture of raw aluminum, and Arconic, which processes aluminum and other metals.
In April 2017, Alcoa announced it will move its headquarters back to Pittsburgh effective September 1.
