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Earl William "Madman" Muntz (January 3, 1914 – June 21, 1987) was an American businessman and engineer who sold and promoted cars and consumer electronics in the United States from the 1930s until his death in 1987. He was a pioneer in television commercials with his oddball "Madman" persona; an alter ego who generated publicity with his unusual costumes, stunts, and outrageous claims. Muntz also pioneered car stereos by creating the Muntz Stereo-Pak, better known as the 4-track cartridge, a predecessor to the 8-track cartridge developed by Lear Industries.
He invented the practice that came to be known as Muntzing, which involved simplifying otherwise complicated electronic devices. Muntz produced and marketed the first black-and-white television receivers to sell for less than $100, and created one of the earliest functional widescreenprojection TVs. He was credited with coining the abbreviation "TV" for television, although the term had earlier been in use in call letters for stations such as WCBS-TV. A high school dropout, Muntz made fortunes by selling automobiles, TV receivers, and car stereos and tapes. A 1968 Los Angeles Times article noted that in one year he sold $72 million worth of cars, that five years later he sold $55 million worth of TV receivers, and that in 1967 he sold $30 million worth of car stereos and tapes.
A fire sprinkler system is an active fire protection method, consisting of a water supply system, providing adequate pressure and flowrate to a water distribution piping system, onto which fire sprinklers are connected. Although historically only used in factories and large commercial buildings, systems for homes and small buildings are now available at a cost-effective price. Fire sprinkler systems are extensively used worldwide, with over 40 million sprinkler heads fitted each year. In buildings completely protected by fire sprinkler systems, over 96% of fires were controlled by fire sprinklers alone.
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The Avrocar S/N 58-7055 (marked AV-7055) on its rollout.
The Avro Canada VZ-9 Avrocar was a VTOL aircraft developed by Avro Canada as part of a secret U.S. military project carried out in the early years of the Cold War. The Avrocar intended to exploit the Coandă effect to provide lift and thrust from a single "turborotor" blowing exhaust out of the rim of the disk-shaped aircraft. In the air, it would have resembled a flying saucer.
Originally designed as a fighter-like aircraft capable of very high speeds and altitudes, the project was repeatedly scaled back over time and the U.S. Air Force eventually abandoned it. Development was then taken up by the U.S. Army for a tactical combat aircraft requirement, a sort of high-performance helicopter. In flight testing, the Avrocar proved to have unresolved thrust and stability problems that limited it to a degraded, low-performance flight envelope; subsequently, the project was cancelled in September 1961. (Full article...)
Project Alberta was formed in March 1945, and consisted of 51 United States Army, Navy, and civilian personnel, including one British scientist. Its mission was three-fold. It first had to design a bomb shape for delivery by air, then procure and assemble it. It supported the ballistic testing work at Wendover Army Air Field, Utah, conducted by the 216th Army Air Forces Base Unit (Project W-47), and the modification of B-29s to carry the bombs (Project Silverplate). After completion of its development and training missions, Project Alberta was attached to the 509th Composite Group at North Field, Tinian, where it prepared facilities, assembled and loaded the weapons, and participated in their use. (Full article...)
The tubes were constructed using the shield method and are each 6,550 feet (2,000 m) long and 15.5 feet (4.7 m) wide. The interiors are lined with cast-iron "rings" formed with concrete. The tubes descend 91 to 95 feet (28 to 29 m) below the mean high water level of the East River, with a maximum gradient of 3.1 percent. During the tunnel's construction, a house at 58 Joralemon Street in Brooklyn was converted into a ventilation building and emergency exit. (Full article...)
Schematic representation of the Dirac delta by a line surmounted by an arrow. The height of the arrow is usually meant to specify the value of any multiplicative constant, which will give the area under the function. The other convention is to write the area next to the arrowhead.
The current understanding of the unit impulse is as a linear functional that maps every continuous function (e.g., ) to its value at zero of its domain (), or as the weak limit of a sequence of bump functions (e.g., ), which are zero over most of the real line, with a tall spike at the origin. Bump functions are thus sometimes called "approximate" or "nascent" delta distributions. (Full article...)
Overhead View of Tehachapi Energy Storage Project, Tehachapi, CA
The Tehachapi Energy Storage Project (TSP) is a 8MW/32MWhlithium-ion battery-based grid energy storage system at the Monolith Substation of Southern California Edison (SCE) in Tehachapi, California, sufficient to power between 1,600 and 2,400 homes for four hours. At the time of commissioning in 2014, it was the largest lithium-ion battery system operating in North America and one of the largest in the world. TSP is considered to be a modern-day energy storage pioneer with significant accomplishments that have proven the viability of utility-scale energy storage using lithium-ion technology. While originally envisioned as a research and development project, TSP operated as a distribution-level resource for SCE and for calendar year 2020, SCE reported that TSP operated in the wholesale energy market with revenue exceeding operating and maintenance costs. In 2021, SCE began the decommissioning of TSP, which was followed by formal decommissioning by state regulators in 2022. The physical dismantlement of TSP is expected to be completed by the end of 2022. (Full article...)
The radius of maximum wind of a tropical cyclone lies just within the eyewall of an intense tropical cyclone, such as Hurricane Isabel from 2003
Originally working mainly on projects in the Middle East, the firm now operates worldwide and in almost all areas of engineering for the built environment, working in 24 locations around the world. (Full article...)
ODB++ is a proprietary CAD-to-CAM data exchange format used in the design and manufacture of electronic devices. Its purpose is to exchange printed circuit board design information between design and manufacturing and between design tools from different EDA/ECAD vendors. It was originally developed by Valor Computerized Systems, Ltd. (acquired in 2010 by Mentor Graphics which was later acquired by Siemens in 2016) as the job description format for their CAM system.
ODB stands for open database, but its openness is disputed, as discussed below. The '++' suffix, evocative of C++, was added in 1997 with the addition of component descriptions. There are two versions of ODB++: the original (now controlled by Mentor) and an XML version called ODB++(X) that Valor developed and donated to the IPC organization in an attempt to merge GenCAM (IPC-2511) and ODB++ into Offspring (IPC-2581). (Full article...)
The Castaing machine is a device used to add lettering and decoration to the edge of a coin. Such lettering was necessitated by counterfeiting and edge clipping, which was a common problem resulting from the uneven and irregular hammered coinage. When Aubin Olivier introduced milled coinage to France, he also developed a method of marking the edges with lettering which would make it possible to detect if metal had been shaved from the edge. This method involved using a collar, into which the metal flowed from the pressure of the press. This technique was slower and more costly than later methods. France abandoned milled coinage in favour of hammering in 1585.
England experimented briefly with milled coinage, but it wasn't until Peter Blondeau brought his method of minting coins there in the mid-seventeenth century that such coinage began in earnest in that country. Blondeau also invented a different method of marking the edge, which was, according to him, faster and less costly than the method pioneered by Olivier. Though Blondeau's exact method was secretive, numismatists have asserted that it likely resembled the later device invented by Jean Castaing. Castaing's machine marked the edges by means of two steel rulers, which, when a coinage blank was forced between them, imprinted legends or designs on its edge. Castaing's device found favour in France, and it was eventually adopted in other nations, including Britain and the United States, but it was eventually phased out by mechanised minting techniques. (Full article...)
Nichols remained with the Manhattan Project after the war until it was taken over by the Atomic Energy Commission in 1947. He was the military liaison officer with the Atomic Energy Commission from 1946 to 1947. After briefly teaching at the United States Military Academy at West Point, he was promoted to major general and became chief of the Armed Forces Special Weapons Project, responsible for the military aspects of atomic weapons, including logistics, handling and training. He was deputy director for the Atomic Energy Matters, Plans and Operations Division of the Army's general staff, and was the senior Army member of the military liaison committee that worked with the Atomic Energy Commission. (Full article...)
3D rendering of a Dyson sphere utilizing large, orbiting panels
A Dyson sphere is a hypothetical megastructure that completely encompasses a star and captures a large percentage of its solar power output. The concept is a thought experiment that attempts to explain how a spacefaring civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone. Because only a tiny fraction of a star's energy emissions reaches the surface of any orbiting planet, building structures encircling a star would enable a civilization to harvest far more energy.
The first contemporary description of the structure was by Olaf Stapledon in his science fiction novel Star Maker (1937), in which he described "every solar system... surrounded by a gauze of light-traps, which focused the escaping solar energy for intelligent use". The concept was later popularized by Freeman Dyson in his 1960 paper "Search for Artificial Stellar Sources of Infrared Radiation". Dyson speculated that such structures would be the logical consequence of the escalating energy needs of a technological civilization and would be a necessity for its long-term survival. He proposed that searching for such structures could lead to the detection of advanced, intelligent extraterrestrial life. Different types of Dyson spheres and their energy-harvesting ability would correspond to levels of technological advancement on the Kardashev scale. (Full article...)
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
An organism that is generated through genetic engineering is considered to be genetically modified (GM) and the resulting entity is a genetically modified organism (GMO). The first GMO was a bacterium generated by Herbert Boyer and Stanley Cohen in 1973. Rudolf Jaenisch created the first GM animal when he inserted foreign DNA into a mouse in 1974. The first company to focus on genetic engineering, Genentech, was founded in 1976 and started the production of human proteins. Genetically engineered human insulin was produced in 1978 and insulin-producing bacteria were commercialised in 1982. Genetically modified food has been sold since 1994, with the release of the Flavr Savr tomato. The Flavr Savr was engineered to have a longer shelf life, but most current GM crops are modified to increase resistance to insects and herbicides. GloFish, the first GMO designed as a pet, was sold in the United States in December 2003. In 2016 salmon modified with a growth hormone were sold. (Full article...)
A chicken gun or flight impact simulator is a large-diameter, compressed-air gun used to fire bird carcasses at aircraft components in order to simulate high-speed bird strikes during the aircraft's flight. Jet engines and aircraft windshields are particularly vulnerable to damage from such strikes, and are the most common target in such tests. Although various species of bird are used in aircraft testing and certification, the device acquired the common name of "chicken gun" as chickens are the most commonly used 'ammunition' owing to their ready availability. (Full article...)
The Churchill Machine Tool Company Limited began as the manufacturing subsidiary of the machine tool importers Charles Churchill & Company Limited founded in the early 1900s by US-born Charles Churchill (1837–1916). Created out of the personal bankruptcy of Charles Churchill, the company developed to become one of the largest British importers of machine tools from the United States and a major manufacturer of such tools, initially under licence and later of its own development.
The original business importing American machine tools into Britain began with Charles Churchill as sole proprietor and later as a partnership with two others. It became a limited company in 1889. In 1906 a separate company, The Churchill Machine Tool Co Ltd, was established with the purpose of adapting tools imported by Charles Churchill & Co. The former expanded, producing American tools under licence and then manufactured tools of its own design, in particular precision surface grinders and similar engineering machinery. In 1918 The Churchill Machine Tool Co relocated its factories onto a single site at Broadheath, near Altrincham. (Full article...)
The following are images from various Engineering-related articles on Wikipedia.
Image 14Design of a turbine requires collaboration of engineers from many fields, as the system involves mechanical, electro-magnetic and chemical processes. The blades, rotor and stator as well as the steam cycle all need to be carefully designed and optimized. (from Engineering)
Image 15Engineers conferring on prototype design, 1954 (from Engineer)
Image 16The application of the steam engine allowed coke to be substituted for charcoal in iron making, lowering the cost of iron, which provided engineers with a new material for building bridges. This bridge was made of cast iron, which was soon displaced by less brittle wrought iron as a structural material (from Engineering)
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