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Vactrain
A vactrain (or vacuum tube train) is a proposed design for very-high-speed rail transportation. It is a maglev (magnetic levitation) line using partly evacuated tubes or tunnels. Reduced air resistance could permit vactrains to travel at very high (hypersonic) speeds with relatively little power—up to . This is 5–6 times the speed of sound in Earth's atmosphere at sea level. 18th century In 1799, George Medhurst of London conceived of and patented an atmospheric railway that could convey people or cargo through pressurized or evacuated tubes. The early atmospheric railways and pneumatic tube transport systems (such as the Dalkey Atmospheric Railway) relied on steam power for propulsion. 19th century In 1888, Michel Verne, son of Jules Verne, imagined a submarine pneumatic tube transport system that could propel a passenger capsule at speeds up to under the Atlantic Ocean (a transatlantic tunnel) in a short story called "An Express of the Future". 20th century The va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatic Tube
Pneumatic tubes (or capsule pipelines, also known as pneumatic tube transport or PTT) are systems that propel cylindrical containers through networks of Tubing (material), tubes by Gas compressor, compressed air or by partial vacuum. They are used for transporting solid objects, as opposed to conventional pipelines which transport fluids. In the late 19th and early 20th centuries, pneumatic tube networks gained acceptance in offices that needed to transport small, urgent packages, such as mail, other paperwork, or money, over relatively short distances, within a building or, at most, within a city. Some installations became quite complex, but have mostly been superseded. However, they have been further developed in the 21st century in places such as hospitals, to send blood samples and the like to clinical laboratory, clinical laboratories for analysis. A small number of pneumatic transportation systems were built for larger cargo, to compete with train and subway systems. However ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maglev
Maglev (derived from '' magnetic levitation'') is a system of rail transport whose rolling stock is levitated by electromagnets rather than rolled on wheels, eliminating rolling resistance. Compared to conventional railways, maglev trains have higher top speeds, superior acceleration and deceleration, lower maintenance costs, improved gradient handling, and lower noise. However, they are more expensive to build, cannot use existing infrastructure, and use more energy at high speeds. Maglev trains have set several speed records. The train speed record of was set by the experimental Japanese L0 Series maglev in 2015. From 2002 until 2021, the record for the highest operational speed of a passenger train of was held by the Shanghai maglev train, which uses German Transrapid technology. The service connects Shanghai Pudong International Airport and the outskirts of central Pudong, Shanghai. At its historical top speed, it covered the distance of in just over 8minutes. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transatlantic Tunnel
A transatlantic tunnel is a theoretical tunnel that would span the Atlantic Ocean between North America and Europe possibly for such purposes as mass transit. Some proposals envision technologically advanced trains reaching speeds of . Most conceptions of the tunnel envision it between the United States and the United Kingdom ‒ or more specifically between New York City and London. The main barriers to constructing such a tunnel are cost (first estimated at $88–175 billion, now updated to $1–20 trillion) as well as limits of current materials science. Existing major tunnels, such as the Channel Tunnel, Seikan Tunnel and the Gotthard Base Tunnel, despite using less expensive technology than any yet proposed for the transatlantic tunnel, may struggle financially. Proposed tunnels Many variations of the concept exist, including a tube above the seabed, a tunnel beneath the ocean floor, or some combination of the two. Vactrain A 1960s proposal has a near-vacuum tube with v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Railway
An atmospheric railway uses differential air pressure to provide power for propulsion of a railway vehicle. A static power source can transmit motive power to the vehicle in this way, avoiding the necessity of carrying mobile power generating equipment. The air pressure, or partial vacuum (i.e., negative relative pressure) can be conveyed to the vehicle in a continuous pipe, where the vehicle carries a piston running in the tube. Some form of re-sealable slot is required to enable the piston to be attached to the vehicle. Alternatively the entire vehicle may act as the piston in a large tube or be coupled Magnetic coupling, electromagnetically to the piston. Several variants of the principle were proposed in the early 19th century, and a number of practical forms were implemented, but all were overcome by unforeseen disadvantages and discontinued within a few years. A modern proprietary system has been developed and is in use for short-distance applications. Porto Alegre Metro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-speed Rail
High-speed rail (HSR) is a type of rail transport network utilising trains that run significantly faster than those of traditional rail, using an integrated system of specialised rolling stock and dedicated railway track, tracks. While there is no single definition or standard that applies worldwide, lines built to handle speeds of at least or upgraded lines of at least are generally considered to be high-speed. The first high-speed rail system, the Tōkaidō Shinkansen, began operations in Honshu, Japan, in 1964. Due to the streamlined spitzer (bullet), spitzer-shaped nose cone of the 0 Series Shinkansen, trains, the system also became known by its English nickname bullet train. Japan's example was followed by several European countries, initially in High-speed rail in Italy, Italy with the Florence–Rome high-speed railway, Direttissima line, followed shortly thereafter by High-speed rail in France, France, High-speed rail in Germany, Germany, and High-speed rail in Spain, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum
A vacuum (: vacuums or vacua) is space devoid of matter. The word is derived from the Latin adjective (neuter ) meaning "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a ''perfect'' vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is considerably lower than atmospheric pressure. The Latin term ''in vacuo'' is used to describe an object that is surrounded by a vacuum. The ''quality'' of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington DC
Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and Federal district of the United States, federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with Maryland to its north and east. It was named after George Washington, the first president of the United States. The district is named for Columbia (personification), Columbia, the female National personification, personification of the nation. The Constitution of the United States, U.S. Constitution in 1789 called for the creation of a federal district under District of Columbia home rule, exclusive jurisdiction of the United States Congress, U.S. Congress. As such, Washington, D.C., is not part of any U.S. state, state, and is not one itself. The Residence Act, adopted on July 16, 1790, approved the creation of the Capital districts and territories, capital district along the Potomac River. The city ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northeast Megalopolis
The Northeast megalopolis, also known as the Northeast Corridor, Acela Corridor, Boston–Washington corridor, BosWash, or BosNYWash, is the most populous megalopolis exclusively within the United States, with slightly over 50 million residents as of 2022. The nickname "BosWash" for the region was first used by futurist Herman Kahn in a 1967 essay. It is the world's largest megalopolis by economic output. Located primarily on the Atlantic Coast in the Northeastern United States, the Northeast megalopolis extends from the northern suburbs of Boston to Washington, D.C., running roughly southwesterly along a section of U.S. Route 1, Interstate 95, and the Northeast Corridor train line. It is sometimes defined more broadly to include other urban regions, including the Richmond and Hampton Roads regions to the south; Portland, Maine, and Manchester, New Hampshire, to the north; and Harrisburg, Pennsylvania, to the west. The region includes many of the nation's most populated me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railway Coupling
A coupling or coupler is a mechanism, typically located at each end of a rolling stock, rail vehicle, that connects them together to form a train. The equipment that connects the couplers to the vehicles is the draft gear or draw gear, which must absorb the stresses of the coupling and the acceleration of the train. Throughout the history of rail vehicles, a variety of coupler designs and types have been developed worldwide. Key design considerations include strength, reliability, easy and efficient handling, and operator safety. Automatic couplers engage automatically when the cars are pushed together. Modern versions not only provide a mechanical connection, but can also couple brake lines and data lines. Different countries use different types of couplers. While North American railroads and China use Janney couplers, railroads in the former Soviet Union use SA3 couplers and the European countries use Scharfenberg coupler, Scharfenberg and Buffers and chain coupler, screw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maryland
Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east, as well as with the Atlantic Ocean to its east, and the national capital and federal district of Washington, D.C. to the southwest. With a total area of , Maryland is the List of U.S. states and territories by area, ninth-smallest state by land area, and its population of 6,177,224 ranks it the List of U.S. states and territories by population, 18th-most populous state and the List of states and territories of the United States by population density, fifth-most densely populated. Maryland's capital city is Annapolis, Maryland, Annapolis, and the state's most populous city is Baltimore. Maryland's coastline was first explored by Europeans in the 16th century. Prior to that, it was inhabited by several Native Americans in the United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mack Reynolds
Dallas McCord "Mack" Reynolds (November 11, 1917 – January 30, 1983) was an American science fiction writer. His pen names included Dallas Ross, Mark Mallory, Clark Collins, Dallas Rose, Guy McCord, Maxine Reynolds, Bob Belmont, and Todd Harding."Mack Reynolds-Summary Bibliography."'' The Internet Speculative Fiction Database.''Stableford, Brian and John Clute"Mack Reynolds."''The Encyclopedia of Science Fiction'', 3d edition (online). Ed. John Clute, David Langford, and Peter Nicholls. 2012. Web. His work focused on socioeconomic speculation, usually expressed in thought-provoking explorations of utopian societies from a radical, sometime satiric perspective. He was a popular author from the 1950s to the 1970s, especially with readers of science fiction and fantasy magazines.Smith, Curtis C. ''Welcome to the Revolution: The Literary Legacy of Mack Reynolds''. San Bernardino, CA: Borgo, 1995. (10). (13). Reynolds was the first author to write an original novel based upon th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
Energy () is the physical quantity, quantitative physical property, property that is transferred to a physical body, body or to a physical system, recognizable in the performance of Work (thermodynamics), work and in the form of heat and light. Energy is a Conservation law, conserved quantity—the law of conservation of energy states that energy can be Energy transformation, converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a Classical field theory, field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, the internal energy contained within a thermodynamic system, and rest energy associated with an object's rest mass. These are not mutual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
