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Topic Review
Space Toilet
A space toilet, or zero gravity toilet is a toilet that can be used in a weightless environment. In the absence of weight, the collection and retention of liquid and solid waste is directed by use of air flow. Since the air used to direct the waste is returned to the cabin, it is filtered beforehand to control odor and cleanse bacteria. In older systems, waste water is vented into space, and any solids are compressed and stored for removal upon landing. More modern systems expose solid waste to vacuum pressures to kill bacteria, which prevents odor problems and kills pathogens.
  • 2.5K
  • 12 Oct 2022
Topic Review
Slipstream (Transformers)
Slipstream is the name of several fictional characters in the Transformers franchise.
  • 2.4K
  • 30 Oct 2022
Topic Review
Autonomous Driving of Electric Vehicles
An autonomous driving system consists of perception, planning, decision, and control, which is illustrated in. The perception subsystem is the basis for other subsystems. It takes data captured from different sensors as input to obtain vehicle’s position and location, also including the size and direction of surrounding objects.
  • 2.4K
  • 17 Sep 2021
Topic Review
Fiat G.55
The Fiat G.55 Centauro (Italian: "Centaur") was a single-engine single-seat World War II fighter aircraft used by the Regia Aeronautica and the A.N.R. (Aeronautica Nazionale Repubblicana) in 1943–1945. It was designed and built in Turin by Fiat. The Fiat G.55 was arguably the best type produced in Italy during World War II, (a subjective claim also frequently made for the Macchi C.205 Veltro as well as for the Reggiane Re.2005 Sagittario) but it did not enter production until 1943, when, after comparative tests against the Messerschmitt Bf 109G and the Focke-Wulf 190, the Luftwaffe itself regarded the Fiat G.55 as "the best Axis fighter". During its short operational service, mostly under the Repubblica Sociale Italiana insignia, after the 8 September 1943 armistice, this powerful, robust and fast aircraft proved itself to be an excellent interceptor at high altitude. In 1944, over Northern Italy, the Centauro clashed with British Supermarine Spitfire, P-51 Mustang, P-47 Thunderbolt and P-38 Lightning, proving to be no easy adversary. Italian fighter pilots liked their Centauro but by the time the war ended, fewer than 300 had been built. By comparison, the Germans produced 35,000 Bf 109s.
  • 2.4K
  • 24 Oct 2022
Topic Review
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 disciplines and firms. Deep foundations can be made out of timber, steel, reinforced concrete or prestressed concrete.
  • 2.4K
  • 23 Nov 2022
Topic Review
Dodge Charger (L-body)
The Dodge Charger (L-body) was a subcompact 3-door hatchback/fastback built by Dodge from 1983 to 1987, and based on Chrysler's front-wheel drive L platform. A companion model, the Plymouth Turismo, was also marketed.
  • 2.4K
  • 19 Oct 2022
Topic Review
Savoia-Marchetti SM.79
The Savoia-Marchetti SM.79 Sparviero (Italian for sparrowhawk) was a three-engined Italian medium bomber developed and manufactured by aviation company Savoia-Marchetti. It could be the best-known Italian aeroplane of the Second World War. The SM.79 was easily recognizable due to its distinctive fuselage dorsal "hump", and was reportedly well liked by its crews, who nicknamed it il gobbo maledetto ("damned hunchback"). The SM.79 had been originally developed during the early 1930s as a cantilever low-wing monoplane employing a combined wood-and-metal structure. It had been designed with the initial intention of producing a swift eight-passenger transport aircraft, capable of besting even the fastest of its contemporaries at that time, however, the project quickly attracted the attention of the Italian government for its potential as an armed combat aircraft. Performing its first flight on 28 September 1934; between 1937 and 1939, early examples of the type established 26 separate world records, qualifying it for some time as being the fastest medium bomber in the world. As such, the SM.79 quickly became regarded as an item of national prestige in Fascist Italy, attracting significant government support and often being deployed as an element of state propaganda. Early on, the aircraft was routinely entered into competitive fly-offs and air races, seeking to capitalise on its advantages, and often emerged victorious in such contests. The SM.79 first saw combat during the Spanish Civil War; in this theatre, it operated without fighter escorts, normally relying on its relatively high speed to evade interception instead. While some issues were identified, and in some cases resolved, the SM.79's performance during the Spanish deployment was encouraging and stimulated demand for the type, including a decision to adopt it as the backbone of Italy's bomber units. Both Yugoslavia and Romania opted to procure the type for their own air services, while large numbers were also procured for the Regia Aeronautica. Almost 600 SM.79-I and –II aircraft were in service when Italy entered the Second World War during May 1940; thereafter, these aircraft were deployed across every theatre of war in which the Italians fought. The SM.79 was operated in various different capacities during the Second World War; initially, the type was used as a transport aircraft and medium bomber. Following pioneering work by the "Special Aerotorpedoes Unit", Italy put the type to work as a torpedo bomber; in this role, the SM.79 achieved notable successes against Allied shipping, particularly in the Mediterranean theater. A specialised drone version of the aircraft, flown by remote control was also developed, although the Armistice with Italy was enacted prior to any operational deployment. It was the most numerous Italian bomber of the Second World War, around some 1,300 aircraft were constructed. The type would remain in Italian service until 1952.
  • 2.4K
  • 30 Nov 2022
Topic Review
Windmill (Sailing Dinghy)
The Windmill is an American sailing dinghy that was designed by Clark Mills as a one-design racer and first built in 1953. The Windmill hull design was developed into the US1 single-handed catboat in 1974.
  • 2.3K
  • 24 Nov 2022
Topic Review
Gorch Fock (1958)
The Gorch Fock is a tall ship of the German Navy (Deutsche Marine). She is the second ship of that name and a sister ship of the Gorch Fock built in 1933. Both ships are named in honour of the German writer Johann Kinau who wrote under the pseudonym "Gorch Fock" and died in the battle of Jutland/Skagerrak in 1916. The modern-day Gorch Fock was built in 1958 and has since then undertaken 146 cruises (as of October 2006), including one tour around the world in 1988. She is sometimes referred to (unofficially) as the Gorch Fock II to distinguish her from her older sister ship. The Gorch Fock is under the command of the Naval Academy in Flensburg-Mürwik.
  • 2.3K
  • 26 Oct 2022
Topic Review
Schiaparelli EDM Lander
Schiaparelli EDM lander [skjapaˈɾɛlːi] was the Entry, Descent and Landing Demonstrator Module (EDM) of the ExoMars programme—a joint mission of the European Space Agency (ESA) and the Russian space agency Roscosmos. It was built in Italy and was intended to test technology for future soft landings on the surface of Mars. It also had a limited but focused science payload that would have measured atmospheric electricity on Mars and local meteorological conditions. Launched together with the ExoMars Trace Gas Orbiter (TGO) on 14 March 2016, Schiaparelli attempted a landing on 19 October 2016. Telemetry signals from Schiaparelli, monitored in real time by the Giant Metrewave Radio Telescope in India (and confirmed by Mars Express), were lost about one minute from the surface during the final landing stages. On 21 October 2016, NASA released an image by the Mars Reconnaissance Orbiter showing what appears to be the lander's crash site. The telemetry data accumulated by the TGO and ESA's Mars Express orbiters are being used to investigate the failure modes of the landing technology employed.
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  • 04 Oct 2022
Topic Review
Ford Maverick (1970)
The Ford Maverick is a compact car manufactured and marketed by Ford for model years 1970–1977 in the United States, originally as a two-door sedan employing a rear-wheel drive platform original to the 1960 Falcon — and subsequently as a four-door sedan on the same platform. The Maverick was also manufactured in Venezuela, Canada, Mexico, and from 1970 to 1979, in Brazil. The name "maverick" was derived from the word for unbranded range animals, and the car's nameplate was stylized to resemble the head of Longhorn cattle.
  • 2.3K
  • 19 Oct 2022
Topic Review
Focke-Wulf Fw 189
The Focke-Wulf Fw 189 Uhu ("Eagle Owl") is a German twin-engine, twin-boom, three-seat tactical reconnaissance and army cooperation aircraft. It first flew in 1938 (Fw 189 V1), entered service in 1940 and was produced until mid-1944. In addition, Focke-Wulf used this airframe in response to a tender request by the RLM for a dedicated ground-attack airplane, and later submitted an armored version for trials. However, the Henschel Hs 129 was selected instead.
  • 2.3K
  • 01 Dec 2022
Topic Review
Mercedes-Benz OM138 Engine
The Mercedes-Benz OM 138 is a diesel engine manufactured by Daimler-Benz: 5,719 were produced between 1935 and 1940[A 1] It was the first diesel engine especially developed and made for a passenger car. The first vehicle powered by the OM 138 was the Mercedes-Benz W 138. The light Mercedes-Benz trucks L 1100 and L 1500 as well as the bus O 1500[A 2] were also offered with the OM 138 as an alternative to an otto engine.
  • 2.2K
  • 24 Oct 2022
Topic Review
Variobahn
The Variobahn, formerly known as the Variotram, is a German-designed model of articulated low-floor tram and light rail vehicle. Since its introduction in 1993, the Variobahn has been manufactured variously by ABB, Adtranz, Bombardier Transportation, and since 2001 by Stadler Rail. As of 2009, 254 trams have been ordered, with an additional 110 on option. A unit costs about €2.5 million. Operators include the Graz Holding, the Bergen Light Rail, the Chemnitz Tramway, Verkehrsverbund Rhein-Ruhr, the Helsinki Tramway, the Rhine Neckar Area Tramway and London Tramlink.
  • 2.2K
  • 09 Nov 2022
Topic Review
Italia (Airship)
The Italia was a semi-rigid airship belonging to the Italian Air Force. It was used by Italian engineer and General Umberto Nobile in his second series of flights around the North Pole. It crashed in 1928, with one confirmed fatality from the crash, one fatality from exposure while awaiting rescue, and the death of six crew members who were trapped in the still-airborne envelope. At the end of the rescue operations there were 17 dead (crew and rescuers).
  • 2.2K
  • 16 Nov 2022
Topic Review
Macchi C.200
The Macchi C.200 Saetta (Italian: Lightning), or MC.200, was a fighter aircraft developed and manufactured by Aeronautica Macchi in Italy. It was operated in various forms by the Regia Aeronautica (Italian Air Force) who used the type throughout the Second World War. The C.200 was designed by Mario Castoldi, Macchi's lead designer, to serve as a modern monoplane fighter aircraft, furnished with retractable landing gear and powered by a radial engine. It possessed excellent maneuverability and the C.200's general flying characteristics left little to be desired. Stability in a high-speed dive was exceptional, but it was underpowered and underarmed in comparison to its contemporaries. Early on, there were a number of crashes caused by stability problems, nearly resulting in the grounding of the type, which was ultimately addressed via aerodynamic modifications to the wing. From the time Italy entered the Second World War on 10 June 1940, until the signing of the armistice of 8 September 1943, the C. 200 flew more operational sorties than any other Italian aircraft. The Saetta saw operational service in Greece, North Africa, Yugoslavia, across the Mediterranean and the Soviet Union (where it obtained an excellent kill to loss ratio of 88 to 15). Its very strong all-metal construction and air-cooled engine made the aircraft ideal for conducting ground attack missions; several units flew it as a fighter-bomber. Over 1,000 aircraft had been constructed by the end of the war.
  • 2.2K
  • 31 Oct 2022
Topic Review
Secondary Treatment
Secondary treatment is a treatment process for wastewater (or sewage) to achieve a certain degree of effluent quality by using a sewage treatment plant with physical phase separation to remove settleable solids and a biological process to remove dissolved and suspended organic compounds. After this kind of treatment, the wastewater may be called as secondary-treated wastewater. Secondary treatment is the portion of a sewage treatment sequence removing dissolved and colloidal compounds measured as biochemical oxygen demand (BOD). Secondary treatment is traditionally applied to the liquid portion of sewage after primary treatment has removed settleable solids and floating material. Secondary treatment is typically performed by indigenous, aquatic microorganisms in a managed aerobic habitat. Bacteria and protozoa consume biodegradable soluble organic contaminants (e.g. sugars, fats, and organic short-chain carbon molecules from human waste, food waste, soaps and detergent) while reproducing to form cells of biological solids. Biological oxidation processes are sensitive to temperature and, between 0 °C and 40 °C, the rate of biological reactions increase with temperature. Most surface aerated vessels operate at between 4 °C and 32 °C.
  • 2.2K
  • 08 Nov 2022
Topic Review
Nordic Folkboat
The Nordic Folkboat (Swedish: Nordisk Folkbåt) is a Swedish sailboat that was designed by Jac Iversen (sv) and Tord Sundén as a racer-cruiser and first built in 1942. Even though Sundén drafted the plans with design ideas provided by Iversen, Sundén was never credited as the actual designer of the boat. The Nordic Folkboat was developed into the Sundén-designed International Folkboat in 1967. The International Folkboat was expressly designed for fibreglass construction. The International 25 and the Olsen 26 are also based upon this design. The Junior Folkboat designed by Erik Salander (båtkonstruktör) (sv) actually dates from 1929. It was originally called the "Juniors Bad" (Junior boat), but was latter renamed because of its strong resemblance to the later and larger Nordic Folkboat.
  • 2.2K
  • 04 Nov 2022
Topic Review
Messerschmitt Me 321
The Messerschmitt Me 321 Gigant was a large German cargo glider developed and used during World War II. Intended to support large scale invasions, the Me 321 saw very limited use due to the low availability of suitable tug aircraft, high vulnerability whilst in flight and the difficult ground handling, both at base and at destination landing sites. The Me 321 was developed, in stages, into the six-engined Messerschmitt Me 323 Gigant, which removed some of the problems with ground handling, but vulnerability to ground fire and aerial attack remained a constant problem during operations of all variants.
  • 2.2K
  • 06 Dec 2022
Topic Review
Diamond DA20
The Diamond DV20/DA20 Katana is an Austrian-designed two-seat tricycle gear general aviation light aircraft. Developed and manufactured by Austrian aircraft manufacturer Diamond Aircraft, it was originally produced in Austria as the DV20. The DV20 shares many features from the earlier Diamond HK36 Super Dimona. It was introduced to service during 1993. During the 1990s, production of the type was commenced at a new facility in Canada in order to meet demand for the type within the North American market. The Canadian-produced aircraft are designated as the DA20. It has been a relative success on the market, having sold in excess of 1,000 aircraft by 2008 and multiple improved variants of the DA20 have been developed. Additionally, it has been further developed into the four-seat Diamond DA40 Star.
  • 2.2K
  • 23 Nov 2022
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