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Nikolaus Otto in 1876, and is also called the Otto cycle. The cycle is characterized by four strokes, or straight movements in a single direction, of the piston
, but may also be found in tubular or radial locks.
When the correct key is inserted, the gaps between the key pins (red) and driver pins (blue) align with the edge of the plug (yellow).
caliper, which is a caliper that uses a vernier scale to interpolate linear measurements. Vernier calipers can measure internal and external dimensions
using, respectively, the uppermost and lower jaws, and also depths, using the depth probe (located at the right end). In this example, the first two digits (2.4) are decided by the location of the zero of the vernier scale in the centimeter scale, and the last digit (0.07), by the first line of the vernier scale that exactly matches a line of the centimeter scale above.
A test firing of twin linear XRS-2200 aerospike engines, originally built for the Lockheed Martin X-33, a next-generation, commercially operated reusable launch vehicle. The aerospike engine is a type of rocket engine that maintains its efficiency across a wide range of altitudes through the use of an aerospike nozzle. A vehicle with an aerospike engine uses 25-30% less fuel at low altitudes, where most missions have the greatest need for thrust.
cylindrical in shape, with two or more contacts. Originally invented for use in telephone switchboards, jack plugs are still widely used, both in the original ¼-inch (6.3 mm) size and in miniaturized versions. The top plug in this image is for stereo connections, while the bottom is for mono
harbours, over the open sea, or through rivers and canals. They also tow barges, disabled ships, and oil rigs
. Equipped with powerful engines producing thousands of horsepower, extensive rigging equipment, and a fender of tires for protection, tugboats can push or tow large vessels with high precision and speed.
mechanical work from pressurized steam and benefit from their high efficiency and high power-to-weight ratio compared to other technologies, leading to their widespread deployment from electricity generation to marine propulsion
propulsion. The paddle wheel was the first form of mechanical propulsion for a boat, but has now been almost entirely superseded by more modern forms of marine propulsion
This diagram of four pulley systems illustrates how increasing the number of pulleys increases the mechanical advantage, making the load easier to lift. MA is the factor by which a mechanism multiplies the force put into it. In this diagram, 100 newtons is required to lift the weight off the ground. Each additional pulley increases the MA such that the four-pulley system only needs 25 newtons to accomplish the same task, but the rope must be pulled four times as far.
(seen to the right), which had just been completed the year before. The addition of a pinnacle and antennas later increased its overall height to 1,472 feet (449 m).
and timing its detonation so that a structure collapses on itself in a matter of seconds, minimizing the physical damage to its immediate surroundings.
A portrait of George Washington Carver, American scientist, botanist, educator and inventor, from 1942. Much of Carver's fame is based on his research into and promotion of alternative crops to cotton, such as peanuts and sweet potatoes. In addition to his work on agricultural extension education for purposes of advocacy of sustainable agriculture and appreciation of plants and nature, Carver's important accomplishments also included improvement of racial relations, mentoring children, poetry, painting, and religion. One of his most important roles was in undermining, through the fame of his achievements and many talents, the widespread stereotype of the time that the black race was intellectually inferior to the white race.
light bulb. Dubbed "The Wizard of Menlo Park" (now Edison, New Jersey) by a newspaper reporter, he was one of the first inventors to apply the principles of mass production and large teamwork to the process of invention, and therefore is often credited with the creation of the first industrial research laboratory. Edison is considered one of the most prolific inventors in history, holding 1,093 U.S. patents in his name
, as well as many patents in the United Kingdom, France and Germany.
track. It is the busiest rapid transit rail system by annual ridership in the Western Hemisphere, and fifth busiest in the world. Its stations are located throughout the boroughs of Manhattan, Brooklyn, Queens and the Bronx. Staten Island has its own rail line
which is not part of the system, but is included in the map as well.
An Agusta A109 rescue helicopter leaves Mount Pilatus, near Lucerne, Switzerland, after recovering a patient. Later renamed AgustaWestland AW109, the A109 is a helicopter manufactured by Agusta (now AgustaWestland) of Italy. It is a light-weight, twin-engine, eight-seat multi-purpose craft.
. Its low retail price and easy availability led to the system becoming the market leader for three years. It remains the best-selling single personal computer model of all time.
Rail transport is a means of conveyance of passengers and goods by way of wheeled vehicles running on rail tracks. The oldest, man-hauled railways date to the 6th century B.C.; the method grew more popular after the introduction of steam locomotives in the 19th century. Here we can see four BNSF GE C44-9W diesel locomotives hauling a mixed freight train along the Columbia River in the US.
sixth generation video game console released by Nintendo beginning in 2001. Meant as a successor to the Nintendo 64, the GameCube sold approximately 22 million units worldwide. It was the third most-successful console of its generation, behind Sony's PlayStation 2 and Microsoft's Xbox. The GameCube was succeeded by the Wii
John Herschel was an English mathematician, astronomer, chemist, inventor, and experimental photographer. He named seven moons of Saturn and four moons of Uranus, invented the cyanotype and actinometer, and wrote extensively on topics including meteorology, physical geography and the telescope.
A self-portrait by the Mars rover Curiosity on October 31, 2012. The mosaic is stitched from a set of 55 images taken by the Mars Hand Lens Imager at "Rocknest," the spot in Gale crater where the mission's first scoop sampling took place. Self-portraits such as this help NASA document the state of the rover and track changes, such as dust accumulation and wheel wear.
four cylinders arranged horizontally in two banks of two cylinders on each side of a central crankcase; they can be used in cars, motorcycles, or aircraft. This type of engine tends to be well-balanced
and have efficient cooling, but is expensive to manufacture and considerably wider than other engines.
A diagram of a typical turbojet engine. Air is compressed as it enters the engine, and is mixed with fuel that burns in the combustion section. Released through the exhaust, the resulting hot gases provide forward thrust and turn the turbines that drive the fan blades of the compressor.
tallest man-made structure in the world, at 829.8 m (2,722 ft). It was designed to be the centerpiece of a large-scale, mixed-use development known as Downtown Dubai
. Construction took over five years, and the skyscraper was officially opened in January 2010.
The Mark IV tank was introduced by the British in May 1917 to fight in World War I. The "female" version, as pictured here, was armed with five machine guns. Production of the Mark IV ceased at the end of the War in 1918. A small number served briefly with other combatants afterwards.
This Mark IV tank, on display in Ashford, Kent, was presented to the town after the end of World War I. The engine was removed to install an electricity substation inside it, though this substation was subsequently removed; the tank's interior is now empty.
A 'K6' model red telephone box outside of St Paul's Cathedral in London. These kiosks for a public telephone were designed by Sir Giles Gilbert Scott and painted "currant red" for easy visibility. Although such telephone boxes ceased production when the KX series was introduced in 1985, they remain a common sight in Britain and some of its colonies, and are considered a British cultural icon.
The Geneva drive is a gear mechanism that translates a continuous rotation into an intermittent rotary motion. The rotating drive wheel has a pin that reaches into a slot of the driven wheel advancing it by one step. The drive wheel also has a raised circular blocking disc that locks the driven wheel in position between steps. Such a mechanism is used in film projectors, watches, and indexing tables, among others.
Bucket-wheel excavators (BWEs) are heavy equipment used in surface mining. The primary function of a BWE is to act as a continuous digging machine in large-scale open pit mining operations. These BWEs were photographed at the Garzweiler surface mine in Germany.
Stockwell, London, designed by Adie, Button and Partners and opened in 1952. The 393-foot-long (120 m) roof structure, seen here, is supported by ten very shallow "two-hinged" arched ribs, between which are cantilevered barrel vaults topped by large skylights. The garage, which could originally hold 200 buses, has been a Grade II* Listed Building
The Sukhoi Superjet 100 is a modern fly-by-wiretwin-engineregional jet with 8 to 108 passenger seats. Development began in 2000; the aircraft had its maiden flight on 19 May 2008 and entered commercial service on 21 April 2011. This aircraft is seen flying off the coast of Italy near Sanremo.
Two Jet Propulsion Laboratory engineers stand with three vehicles, providing a size comparison of three generations of Mars rovers. Front and center is the flight spare for the first Mars rover, Sojourner, which landed on Mars in 1997 as part of the Mars Pathfinder Project. On the left is a Mars Exploration Rover test vehicle, a working sibling to Spirit and Opportunity, which landed on Mars in 2004. On the right is a test rover for the Mars Science Laboratory, which landed Curiosity on Mars in 2012.
A windmill is a mill that converts the energy of wind into rotational energy by means of vanes called sails or blades. Traditional windmills were often used to mill grain, pump water, or both. Most modern windmills take the form of wind turbines used to generate electricity, or windpumps used to pump water, either for land drainage or to extract groundwater.
Here, the smock mill Goliath is viewed in front of the wind farm Growind in Eemshaven in the Netherlands.
Wiesen, Switzerland. Designed by Henning Friedrich, then the chief engineer of the Rhaetian Railway, it was built between 1906 and 1909 by the contractor G. Marasi (Westermann & Cie, Zürich) under the supervision of P. Salaz and Hans Studer (RhB). The Rhaetian Railway still owns and uses the viaduct today for regular service with 29 passenger trains per day. An important element of the Davos–Filisur railway, the viaduct is 88.9 metres (292 ft) high, 210 metres (690 ft) long, and has a main span of 55 metres (180 ft). In 1926, the viaduct was the inspiration for Ernst Ludwig Kirchner
greyscale picture of the state of the coffee pot. The webcam was shut down on 22 August 2001, following the Computer Laboratory's move to the William Gates Building
(opposing ends joined by a frame). The spindle is a very accurately machined screw and the object to be measured is placed between the spindle and the anvil. The spindle is moved by turning the ratchet knob or thimble until the object to be measured is lightly touched by both the spindle and the anvil.
Apple Bandai Pippin is a multimedia technology console designed by Apple Computer based on the Apple Pippin platform, and produced by Bandai. Only 100,000 of the consoles were produced between its 1996 release and 1997 discontinuation. The Bandai Pippin was intended to create an inexpensive computer aimed mostly at playing CD-based multimedia software, especially games, but also functioning as a thin client
A diagram showing a side and underside view of an 18-wheeler semi-trailer truck with an enclosed cargo space. The underside view shows the arrangement of the wheels, and in blue, the axles, drive shaft, and differentials.
The numbered parts are:
tractor unit
semi-trailer (detachable)
engine compartment
cabin
sleeper (not present in all trucks)
air dam
fuel tanks
fifth-wheel coupling
enclosed cargo space
landing gear (legs for when semi-trailer is detached)
fuel dispensers, which distribute fuels such as gasoline and diesel into the tanks within vehicles and calculate the financial cost of the fuel transferred. Filling stations may also include air compressors and electricity sockets, which may inflate tyres or offer charging stations. Many filling stations also incorporate a convenience store
, where customers can purchase snacks and other goods.
6th Minnesota Volunteer Infantry Regiment during the American Civil War. Crooks laid out the initial ten-mile track between Minneapolis and St. Paul on which the locomotive operated. It was retired from regular service in 1897, but operated special services for several further decades. It is now in the Lake Superior Railroad Museum
Photograph credit: Unknown; restored by Adam Cuerden
George Washington Carver (1860s–1943) was an American agricultural scientist and inventor. Born into slavery in Diamond, Missouri, he was raised by his master Moses Carver after being emancipated, having been separated from his parents as an infant during a kidnapping incident. After college, Carver became a professor at Tuskegee Institute, where he developed techniques to improve soils depleted by repeated plantings of cotton. He wanted poor farmers to grow alternative crops, such as peanuts and sweet potatoes, as a source of their own food and to improve their quality of life. Carver spent years developing and promoting products made from peanuts, although none became commercially successful. Apart from his work to improve the lives of farmers, he was also a leader in promoting environmentalism. Carver received numerous honors for his work, including the NAACP's Spingarn Medal. In an era of very high racial polarization, his fame reached beyond the black community; he was widely recognized and praised in the white community for his many achievements and talents. In 1941, Time magazine dubbed Carver a "black Leonardo".
This picture of Carver was taken around 1910 and is in the collection of the Tuskegee University archives.
, she later took advanced engineering classes and, in 1958, became NASA's first black female engineer.
After 34 years at NASA, Jackson had earned the most senior engineering title available. Realizing that she could not earn further promotions without becoming a supervisor, she accepted a demotion to become a manager of the Federal Women's Program in the NASA Office of Equal Opportunity Programs, as well as of the Affirmative Action Program. In this role, she worked to influence both the hiring and promotion of women in NASA's science, engineering and mathematics careers. She was portrayed by Janelle Monáe as a lead character in the 2016 film Hidden Figures. This picture, taken in 1980, shows Jackson working at NASA Langley.
four-cylinder engine, redlined at 14,200 rpm, it delivers 133.6 kW (179.2 hp; 181.6 PS) to the rear wheel, making it the most powerful motorcycle in the class. Rubén Xaus and Troy Corser rode the bike for its inaugural Superbike World Championship in 2009, gaining highest finishes of fifth and seventh respectively, but it achieved greater success in the 2010 FIM Superstock 1000 championship season, with rider Ayrton Badovini
Photograph credit: John Masterson, CSIRO; restored by Bammesk
The Australia Telescope Compact Array is a radio telescope operated by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) at the Paul Wild Observatory, 25 km (16 mi) west of the town of Narrabri in New South Wales, Australia. The telescope is an array of six identical dishes each 22 metres (72 ft) in diameter, which commonly operate in aperture synthesis mode to produce images from radio waves. Five of the dishes can be moved along a 3-kilometre (2 mi) railway track; the sixth is situated three kilometres west of the end of the main track. Each dish weighs about 270 tonnes (270 long tons; 300 short tons).
This photograph, showing five of the Australia Telescope Compact Array's dishes, was taken around 1984, in the late phase of the construction process. It is a long-exposure photograph taken in darkness in the late evening; during the exposure, the photographer, John Masterson, walked around the dishes firing off over 130 flashes using a hand-held flash gun.
A hybrid-propellant rocket is a rocket with an engine that uses propellants in two different phases, one solid and the other gaseous or liquid. The concept can be traced back to at least the 1930s.
This picture shows a transparent 3D-printed hybrid-rocket fuel grain with dual helical fuel ports, a post-combustion chamber, and a de Laval nozzle, photographed prior to the hot-fire test. The motor used nitrous oxide as the oxidizer and Pyrodex pellets for the igniter.
annealed copper conductors. Each of the current-carrying conductors in the "core" is insulated by an individual thermoplastic sheath, coloured to indicate the purpose of the conductor concerned. The protective earth conductor
may also be covered with insulation, although, in some countries, this conductor may be left as bare copper. The type of thermoplastic, the dimensions of the conductors and the colour of their individual insulation are specified by the regulatory bodies in the various countries concerned.
propeller, which increases performance and decreases cabin noise. In a passenger configuration, the pressurized cabin is typically fitted with highly finished interiors, featuring luxury materials such as leather and wood veneers.
The Soyuz MS is the latest revision of the Russian spacecraft series Soyuz. It is an evolution of the Soyuz TMA-M, with modernization mostly concentrated on its communications and navigation subsystems. The spacecraft is used by Roscosmos for human spaceflight. The Soyuz MS has minimal external changes with respect to the Soyuz TMA-M, mostly limited to antennas and sensors, as well as the thruster placement. The first launch, Soyuz MS-01, took place on 7 July 2016 aboard a Soyuz-FG launch vehicle towards the International Space Station. This exploded-view diagram illustrates and labels various components of the Soyuz MS spacecraft and the Soyuz-FG rocket.
The Walchensee Hydroelectric Power Station is a storage power station in Bavaria, Germany. The turbines, seen here, are fed by water from the Walchensee which is then released into the Kochelsee. The power station uses the hydraulic head of about 200 metres (660 ft) between the two natural lakes, and water from the Rißbach river is also used to augment the supply. The installed capacity is 124 MW with an annual production of 300 GWh; this is one of the largest of such power plants in Germany.
An escalator is a moving staircase for carrying people between floors of a building. The device consists of a motor-driven chain of individual, linked steps that move up or down on tracks, allowing the step treads to remain horizontal.
A wheel is a circular component that is intended to rotate on an axial bearing. The wheel is one of the main components of the wheel and axle which is one of the six simple machines.
Wearable computers, also known as wearables or body-borne computers, are small computing devices (nowadays usually electronic) that are worn under, with, or on top of clothing.
Stimulated emission is the process by which an incoming photon of a specific frequency can interact with an excited atomic electron (or other excited molecular state), causing it to drop to a lower energy level.
A laser pointer is a small handheld device with a power source (usually a battery) and a laser diode emitting a very narrow coherent low-powered laser beam of visible light.