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Hangar One (Moffett Field, California)
Hangar One is one of the world's largest freestanding structures, covering at Moffett Field near Mountain View, California in the San Francisco Bay Area. The massive hangar has long been one of the most recognizable landmarks of California's Silicon Valley. It was built in the 1930s as a naval airship hangar for and is now part of the NASA Ames Research Center. Design and construction Designed by German air ship and structural engineer Dr. Karl Arnstein, Vice President and Director of Engineering for the Goodyear Zeppelin Corporation of Akron, Ohio, in collaboration with Wilbur Watson Associates Architects and Engineers of Cleveland, Ohio, Hangar One is constructed on a network of steel girders sheathed with galvanized steel. It rests firmly upon a reinforced pad anchored to concrete pilings. The floor covers and can accommodate six American football fields. The airship hangar measures long and wide. The building has an aerodynamic architecture. Its walls curve inward ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Clara County, California
Santa Clara County, officially the County of Santa Clara, is the sixth-most populous county in the U.S. state of California, with a population of 1,936,259, as of the 2020 United States Census, 2020 census. Santa Clara County and neighboring San Benito County, California, San Benito County together form the U.S. Census Bureau's San Jose-Sunnyvale-Santa Clara metropolitan statistical area, which is part of the larger San Jose-San Francisco-Oakland, California, Oakland combined statistical area. Santa Clara is the most populous county in the San Francisco Bay Area and in Northern California. The county seat and largest city is San Jose, California, San Jose, the List of United States cities by population, 10th-most populous city in the United States, List of cities and towns in California, California's third-most populous city and the List of cities and towns in the San Francisco Bay Area, most populous city in the San Francisco Bay Area. Home to Silicon Valley, Santa Clara County ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Foundation
A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. A pile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site. There are many reasons that a geotechnical engineer would recommend a deep foundation over a shallow foundation, such as for a skyscraper. Some of the common reasons are very large design loads, a poor soil at shallow depth, or site constraints like property lines. There are different terms used to describe different types of deep foundations including the pile (which is analogous to a pole), the pier (which is analogous to a column), drilled shafts, and caissons. Piles are generally driven into the ground in situ; other deep foundations are typically put in place using excavation and drilling. The naming conventions may vary between engineering discip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Italian Air Force
, colours = , colours_label = , march = (Ordinance March of the Air Force) by Alberto Di Miniello , mascot = , anniversaries = 28 March (Air Force Day) , equipment = , equipment_label = , battles = , decorations = , battle_honours = , battle_honours_label = , flying_hours = , website = , commander1 = Generale di squadra Luca Goretti , commander1_label = Chief of Staff of Air Force , notable_commanders = , identification_symbol = , identification_symbol_label = Roundel , identification_symbol_2 = , identification_symbol_2_label = Roundel Low Visibility , aircraft_attack = Panavia Tornado, AMX International AMX , aircraft_bomber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugène Freyssinet
Eugène Freyssinet () (13 July 1879 – 8 June 1962) was a French structural and civil engineer. He was the major pioneer of prestressed concrete. Biography Freyssinet was born in at Objat, Corrèze, France. He worked in the ''École Nationale des Ponts et Chaussées'' in Paris, France where he designed several bridges until the First World War intervened. His tutors included Charles Rabut. He served in the French Army from 1904 to 1907 and again from 1914 to 1918 as a road engineer. His most significant early bridge was the three span Pont le Veurdre near Vichy, built in 1911. At the time, the 72.5 metre (238 ft) spans were the longest so far constructed in France although Grafton Bridge a 97.6 metre reinforced concrete bridge had been opened in April 1910 and the Rocky River Bridge in Cleveland Ohio, an 85.34 metre unreinforced bridge had been opened in October 1910. Freyssinet's proposal was for three reinforced concrete truss spans, and was significantly less expensi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orly Air Base
Orly Air Base was a United States Air Force Facility during the early part of the Cold War, located at Aéroport de Paris-Orly, south of Paris, France. The American Air Base was located on the north side of the airport, in an area east of the current-day Val-de-Marne/Essonne. The facility was first developed as a military airfield by the Air Service, American Expeditionary Forces (AEF) during World War I. With the end of the war, in 1920 it was eventually developed into a civil airport. After the 1940 Battle of France, the occupying German Luftwaffe seized the facility and used it as a military airfield. In 1944, the Germans were driven out and it subsequently became an Advanced Landing Ground (ALG) designated A-47 for the United States Army Air Forces Ninth Air Force. Rebuilt after the war as a joint civil/military airfield, the primary use of the base was to support Supreme Headquarters Allied Powers Europe (SHAPE) at Rocquencourt. Secondary functions were as a personnel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goodyear Airdock
The Goodyear Airdock is a construction and storage airship hangar in Akron, Ohio. At its completion in 1929, it was the largest building in the world without interior supports. Description The building has a unique shape which has been described as "half a silkworm's cocoon, cut in half the long way." It is 1,175 feet (358.14 m) long, 325 feet (99.06 m) wide, and 211 feet (64.31 m) high, supported by 13 steel arches. There is 364,000 square feet (34 000 m²) of unobstructed floor space, or an area larger than 8 football fields side-by-side. The airdock has a volume of 55 million cubic feet (or about 1.5 million cubic meters). A control tower and radio aerial sit at its northeast end. At each end of the building are two huge semi-spherical doors that each weigh 600 tons (544 000 kg). At the top, the doors are fastened by hollow forged pins 17 inches (43 cm) in diameter and six feet (1.83 m) long. The doors roll on 40 wheels along specially-designed curved railroad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airship
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 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 available for airships in that country. Most airships built since the 1960s have used helium, though some have used hot air.A few airships after World War II used hydrogen. The first British airship to use helium was the ''Chitty Bang Bang'' of 1967. The envelope of an airship may form the gasbag, or it may contain a number of gas-filled cells. An airship also has engines, crew, and optionally also payload accommodation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Gauge
A standard-gauge railway is a railway with a track gauge of . The standard gauge is also called Stephenson gauge (after George Stephenson), International gauge, UIC gauge, uniform gauge, normal gauge and European gauge in Europe, and SGR in East Africa. It is the most widely used track gauge around the world, with approximately 55% of the lines in the world using it. All high-speed rail lines use standard gauge except those in Russia, Finland, and Uzbekistan. The distance between the inside edges of the rails is defined to be 1435 mm except in the United States and on some heritage British lines, where it is defined in U.S. customary/Imperial units as exactly "four feet eight and one half inches" which is equivalent to 1435.1mm. History As railways developed and expanded, one of the key issues was the track gauge (the distance, or width, between the inner sides of the rails) to be used. Different railways used different gauges, and where rails of different gauge met – ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Park Service
The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational properties with various title designations. The U.S. Congress created the agency on August 25, 1916, through the National Park Service Organic Act. It is headquartered in Washington, D.C., within the main headquarters of the Department of the Interior. The NPS employs approximately 20,000 people in 423 individual units covering over 85 million acres in all 50 states, the District of Columbia, and US territories. As of 2019, they had more than 279,000 volunteers. The agency is charged with a dual role of preserving the ecological and historical integrity of the places entrusted to its management while also making them available and accessible for public use and enjoyment. History Yellowstone National Park was created as the first national par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turbulence
In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between those layers. Turbulence is commonly observed in everyday phenomena such as surf, fast flowing rivers, billowing storm clouds, or smoke from a chimney, and most fluid flows occurring in nature or created in engineering applications are turbulent. Turbulence is caused by excessive kinetic energy in parts of a fluid flow, which overcomes the damping effect of the fluid's viscosity. For this reason turbulence is commonly realized in low viscosity fluids. In general terms, in turbulent flow, unsteady vortices appear of many sizes which interact with each other, consequently drag due to friction effects increases. This increases the energy needed to pump fluid through a pipe. The onset of turbulence can be predicted by the dimensionless Rey ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve Shell
A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two hinged parts or ''valves''. Bivalves are very common in essentially all aquatic locales, including saltwater, brackish water, and freshwater. The shells of bivalves commonly wash up on beaches (often as separate valves) and along the edges of lakes, rivers, and streams. Bivalves by definition possess two shells or ''valves'', a "right valve" and a "left valve", that are joined by a ligament. The two valves usually articulate with one another using structures known as "teeth" which are situated along the hinge line. In many bivalve shells, the two valves are symmetrical along the hinge line—when truly symmetrical, such an animal is said to be ''equivalved''; if the valves vary from each other in size or shape, ''inequivalved''. If symmetrical front-to-back, the valves are said to be ''equilateral'', and are otherwise considered ''in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
