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Tacoma Narrows Bridge (1940)
The 1940 Tacoma Narrows Bridge, the first Tacoma Narrows Bridge, was a suspension bridge in the U.S. state of Washington that spanned the Tacoma Narrows strait of Puget Sound between Tacoma and the Kitsap Peninsula. It opened to traffic on July 1, 1940, and dramatically collapsed into Puget Sound on November 7 of the same year. The bridge's collapse has been described as "spectacular" and in subsequent decades "has attracted the attention of engineers, physicists, and mathematicians". Throughout its short existence, it was the world's third-longest suspension bridge by main span, behind the Golden Gate Bridge and the George Washington Bridge. Construction began in September 1938. From the time the deck was built, it began to move vertically in windy conditions, so construction workers nicknamed the bridge Galloping Gertie. The motion continued after the bridge opened to the public, despite several damping measures. The bridge's main span finally collapsed in winds on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leon Moisseiff
Leon Solomon Moisseiff (November 10, 1872 – September 3, 1943) was a leading suspension bridge engineer in the United States in the 1920s and 1930s. He was awarded The Franklin Institute's Louis E. Levy Medal in 1933. His developments of the theory of suspension bridges are eclipsed by the dramatic failure of the Tacoma Narrows Suspension Bridge, his design, four months after its completion in 1940. The failure was filmed, and is shown to engineering students as a reminder of the possibility of failure, and to avoid hubris. Biography Moisseiff was born in Riga, Latvia (at the time, Russian Empire), to a Jewish family. |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mackinac Bridge
The Mackinac Bridge ( ) is a suspension bridge spanning the Straits of Mackinac, connecting the Upper and Lower peninsulas of the U.S. state of Michigan. Opened in 1957, the bridge (familiarly known as "Big Mac" and "Mighty Mac") is the world's 27th-longest main span and the longest suspension bridge between anchorages in the Western Hemisphere. The Mackinac Bridge is part of Interstate 75 (I-75) and the Lake Michigan and Huron components of the Great Lakes Circle Tour across the straits; it is also a segment of the U.S. North Country National Scenic Trail. The bridge connects the city of St. Ignace on the north end with the village of Mackinaw City on the south. Envisioned since the 1880s, the bridge was designed by the engineer David B. Steinman and completed in 1957 only after many decades of struggles to begin construction. Length The bridge opened on November 1, 1957, connecting two peninsulas linked for decades by ferries. At the time, the bridge was formally d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David B
David Robert Jones (8 January 194710 January 2016), known professionally as David Bowie ( ), was an English singer-songwriter and actor. A leading figure in the music industry, he is regarded as one of the most influential musicians of the 20th century. Bowie was acclaimed by critics and musicians, particularly for his innovative work during the 1970s. His career was marked by reinvention and visual presentation, and his music and stagecraft had a significant impact on popular music. Bowie developed an interest in music from an early age. He studied art, music and design before embarking on a professional career as a musician in 1963. "Space Oddity", released in 1969, was his first top-five entry on the UK Singles Chart. After a period of experimentation, he re-emerged in 1972 during the glam rock era with his flamboyant and androgynous alter ego Ziggy Stardust (character), Ziggy Stardust. The character was spearheaded by the success of Bowie's single "Starman (song), Starma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Strauss (engineer)
Joseph Baermann Strauss (January 9, 1870 – May 16, 1938) was an American structural engineer who revolutionized the design of bascule bridges. He was the chief engineer of the Golden Gate Bridge, a suspension bridge. Life, beginnings and death He was born in Cincinnati, Ohio, to an artistic family of German-Jewish ancestry. His mother was a pianist, and his father, Raphael Strauss, was a writer and painter. He graduated from the University of Cincinnati in 1892 with a degree in civil engineering. He served as both class poet and president, and was a brother of the Sigma Alpha Epsilon fraternity. Strauss had many hobbies. One of these included poetry. After completion of the Golden Gate Bridge he returned to his passion of poetry and wrote his most recognizable poem "The Mighty Task is Done". He also wrote "The Redwoods", and his "Sequoia" can still be purchased by tourists visiting the California redwoods. He died in Los Angeles, California, just one year after the Golden Gat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Scientist
__NOTOC__ ''American Scientist'' (informally abbreviated ''AmSci'') is an American bimonthly science and technology magazine published since 1913 by Sigma Xi, The Scientific Research Society. In the beginning of 2000s the headquarters was in New Haven, CT. Each issue includes feature articles written by prominent scientists and engineers who review research in fields from molecular biology to computer engineering. Each issue also includes the work of cartoonists, including those of Sidney Harris, Benita Epstein Benita L. Epstein is a prolific gag cartoonist for magazines, greeting cards, websites and newspapers. She was a regular contributor to the comic strip ''Six Chix'', distributed by King Features Syndicate. Before becoming a cartoonist, Epstein ea ..., and Mark Heath. Also included is the ''Scientists' Nightstand'' that reviews a vast range of science-related books and novels. ''American Scientist Online'' () was launched in May 2003. References External links * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chamber Of Commerce
A chamber of commerce, or board of trade, is a form of business network. For example, a local organization of businesses whose goal is to further the interests of businesses. Business owners in towns and cities form these local societies to advocate on behalf of the business community. Local businesses are members, and they elect a board of directors or executive council to set policy for the chamber. The board or council then hires a President, CEO, or Executive Director, plus staffing appropriate to size, to run the organization. A chamber of commerce may be a voluntary or a mandatory association of business firms belonging to different trades and industries. They serve as spokespeople and representatives of a business community. They differ from country to country. History The first chamber of commerce was founded in 1599 in Marseille, France, as the "Chambre de Commerce". Another official chamber of commerce followed 65 years later, probably in Bruges, then part of the S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trestle Bridge
A trestle bridge is a bridge composed of a number of short spans supported by closely spaced frames. A trestle (sometimes tressel) is a rigid frame used as a support, historically a tripod used to support a stool or a pair of isosceles triangles joined at their apices by a plank or beam such as the support structure for a trestle table. Each supporting frame is a bent. A trestle differs from a viaduct in that viaducts have towers that support much longer spans and typically have a higher elevation. Timber and iron trestles (i.e. bridges) were extensively used in the 19th century, the former making up from 1 to 3 percent of the total length of the average railroad. In the 21st century, steel and sometimes concrete trestles are commonly used to bridge particularly deep valleys, while timber trestles remain common in certain areas. Many timber trestles were built in the 19th and early 20th centuries with the expectation that they would be temporary. Timber trestles were use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Pacific Railway
The Northern Pacific Railway was a transcontinental railroad that operated across the northern tier of the western United States, from Minnesota to the Pacific Northwest. It was approved by Congress in 1864 and given nearly of land grants, which it used to raise money in Europe for construction. Construction began in 1870 and the main line opened all the way from the Great Lakes to the Pacific when former President Ulysses S. Grant drove in the final "golden spike" in western Montana on September 8, 1883. The railroad had about of track and served a large area, including extensive trackage in the states of Idaho, Minnesota, Montana, North Dakota, Oregon, Washington, and Wisconsin. In addition, the NP had an international branch to Winnipeg, Manitoba, Canada. The main activities were shipping wheat and other farm products, cattle, timber, and minerals; bringing in consumer goods, transporting passengers; and selling land. The Northern Pacific was headquartered in Minnesota, fir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamics
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics. The term ''aerodynamics'' is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving Aircraft#Heavier than air – aerodynes, heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torsion (mechanics)
In the field of solid mechanics, torsion is the twisting of an object due to an applied torque. Torsion is expressed in either the pascal (Pa), an SI unit for newtons per square metre, or in pounds per square inch (psi) while torque is expressed in newton metres (N·m) or foot-pound force (ft·lbf). In sections perpendicular to the torque axis, the resultant shear stress in this section is perpendicular to the radius. In non-circular cross-sections, twisting is accompanied by a distortion called warping, in which transverse sections do not remain plane. For shafts of uniform cross-section unrestrained against warping, the torsion is: : T = \frac \tau= \frac G \varphi where: * ''T'' is the applied torque or moment of torsion in Nm. * \tau (tau) is the maximum shear stress at the outer surface * ''J''T is the torsion constant for the section. For circular rods, and tubes with constant wall thickness, it is equal to the polar moment of inertia of the section, but for other shape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aeroelasticity
Aeroelasticity is the branch of physics and engineering studying the interactions between the inertial, elastic, and aerodynamic forces occurring while an elastic body is exposed to a fluid flow. The study of aeroelasticity may be broadly classified into two fields: ''static aeroelasticity'' dealing with the static or steady state response of an elastic body to a fluid flow; and ''dynamic aeroelasticity'' dealing with the body's dynamic (typically vibrational) response. Aircraft are prone to aeroelastic effects because they need to be lightweight and withstand large aerodynamic loads. Aircraft are designed to avoid the following aeroelastic problems: # divergence where the aerodynamic forces increase the angle of attack of a wing which further increases the force; # control reversal where control activation produces an opposite aerodynamic moment that reduces, or in extreme cases, reverses the control effectiveness; and # flutter which is the uncontained vibration that can lead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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