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Characteristics, Impacts and Trends of Urban Transportation
Economic growth, urban development and the prosperity of the automobile industry have driven a huge shift in global urban transportation from walking to public transportation and then to automobiles. Private mobility has become an important part of residents’ daily trips. Cities, especially automobile-dependent cities, face a variety of negative impacts such as increased commuting distances, higher congestion costs, traffic accidents, traffic pollution including climate change, etc. Therefore, how to balance the relationship between people’s growing demand for private motorization with the development of urbanization, modernization and motorization and the huge economic, social and environmental costs brought about by them, so as to realize the sustainable development of cities and transportation, is the main problem facing cities around the world. The entry focuses on trends in the sustainable development of urban transportation such as restrictions in private car ownership and use, electrification of urban transportation, intelligent transportation systems (including shared mobility, customized buses and Mobility as a Service/MaaS) and transit-oriented development (TOD). China, as the largest global automobile producer and consumer, represents and leads the growth and evolution of other emerging countries.
  • 4.9K
  • 15 Jun 2022
Topic Review
Aircraft Livery
An aircraft livery is a set of comprehensive insignia comprising color, graphic, and typographical identifiers which operators (airlines, governments, Air force s and occasionally private and corporate owners) apply to their aircraft. As aircraft liveries evolved in the years after the Second World War, they became a leading subset of the emerging disciplines of corporate identity and branding and among the most prominent examples of fashion. They have provided an arena for the work of distinguished designers and eminent lay people like Raymond Loewy, Alexander Girard, and Jacqueline Kennedy Onassis. The term is an adaptation of the word livery: the uniform-style clothing worn by servants of wealthy families and government representatives until the early/mid-20th century. With the advent of stagecoaches, railway trains, and steamships, the term livery spread to their decoration. Since the 1950s, elements of airline liveries permeated ground vehicles, advertising, proprietary airport furniture, airline promotional materials and aircrew uniforms in an increasingly integrated manner, spreading to airline websites in the 1990s. Since the 1950s and 60s, aircraft liveries have usually been uniform livery across an entire fleet. One-off custom-designs might be applied from time to time to individual fleet members to highlight set occasions.
  • 4.9K
  • 21 Oct 2022
Topic Review
Messerschmitt Me 323
The Messerschmitt Me 323 Gigant ("Giant") was a German military transport aircraft of World War II. It was a powered variant of the Me 321 military glider and was the largest land-based transport aircraft of the war. A total of 213 are recorded as having been made, 15 being converted from the Me 321.
  • 4.9K
  • 17 Oct 2022
Topic Review
Daihatsu Rocky
The Daihatsu Rocky (Japanese: ダイハツ・ロッキー, Daihatsu Rokkī) is an automobile nameplate used by Daihatsu for their lineup of SUVs. The nameplate was originally used as a ladder frame-based mini SUV that was sold in Japan and some international markets between 1989 and 2002. It was gradually replaced by the introduction of Terios in 1997. Beginning in 2019, the Rocky nameplate returned to Japan as a subcompact crossover SUV that replaces the Be‣go and is also rebadged and sold under Toyota brand as the Toyota Raize (Japanese: トヨタ・ライズ, Toyota Raizu).
  • 4.8K
  • 27 Oct 2022
Topic Review
Photonic Laser Thruster
A photonic laser thruster (PLT) is an amplified photonic propulsion thruster for space propulsion that works on the principle of a photon-pushed sail, generating thrust directly from the momentum of a photon from a laser reflected from a mirror. The thruster, invented by Young K. Bae differs from other solar sail and laser propulsion thrusters in that an amplification process is used, in which the incident beam is re-used by being reflected by a stationary mirror, with an amplification stage at each reflection. Because of the recycling of energy, the photonic laser thruster has been demonstrated to be more energy efficient than other laser-pushed sail concepts. The near-term usage of the photonic laser thruster the earth-orbit applications include propellant-free and thrust-plume-contamination-free spacecraft maneuvering for precision formation flying, large optical and RF synthetic aperture construction, and stationkeeping. The usage of the photonic laser thruster for main space propulsion would require scaling-up of the laser power and controlling laser diffraction over interplanetary and interstellar distances. Photonic laser thrusters have a very high specific impulse, and can permit spacecraft to reach much higher speeds that approach a fraction of the light speed, unlike conventional rockets, which are limited by the Tsiolkovsky rocket equation.
  • 4.7K
  • 01 Nov 2022
Topic Review
Embraer KC-390
The Embraer KC-390 is a medium-size, twin-engine jet-powered military transport aircraft under development by Brazil ian aerospace manufacturer Embraer, able to perform aerial refuelling and to transport cargo and troops. It is the heaviest aircraft that the company has made to date, and will be able to transport up to 26 tonnes (29 tons) of cargo, including wheeled armoured fighting vehicles.
  • 4.6K
  • 31 Oct 2022
Topic Review
Autonomous Cruise Control System
Autonomous cruise control (ACC; also called adaptive cruise control, radar cruise control, traffic-aware cruise control or dynamic radar cruise control) is an optional cruise control system for road vehicles that automatically adjusts the vehicle speed to maintain a safe distance from vehicles ahead. Control is based on sensor information from on-board sensors. (No existing system makes use of satellite or roadside infrastructures nor of cooperative support from other vehicles.) Cooperative Adaptive Cruise Control (CACC) further extends the automation of navigation by using information gathered from fixed infrastructure such as satellites and roadside beacons, or mobile infrastructure such as reflectors or transmitters on the back of other vehicles. Such systems may use a radar or laser sensor or a stereo camera setup allowing the vehicle to brake when it detects the car is approaching another vehicle ahead, then accelerate when traffic allows it to. ACC technology is widely regarded as a key component of any future generations of intelligent cars. They impact driver safety and convenience as well as increasing capacity of roads by maintaining optimal separation between vehicles and reducing driver errors. Vehicles with autonomous cruise control are considered a Level 1 autonomous car, as defined by SAE International. Adaptive cruise Control does not provide full autonomy: the system only provides some help to the driver, but does not drive the car by itself. Europe is the main market for Adaptative Cruise control, in 2016.
  • 4.6K
  • 08 Nov 2022
Topic Review
List of Aircraft (H)
This is a list of aircraft in alphabetical order beginning with 'H'.
  • 4.5K
  • 08 Nov 2022
Topic Review
List of AEW&C Aircraft Operators
Airborne early warning and control (AEW&C) aircraft are airborne radar systems designed to detect and track aircraft, missiles, ships and vehicles and provide command and control to direct friendly forces. Some operators, such as the Royal Air Force refer to such aircraft as Airborne early warning (AEW), while others reserve the shorter name for AEW aircraft lacking command and control facilities.
  • 4.5K
  • 03 Nov 2022
Topic Review
List of Oldest Surviving Ships
This is a list of the oldest ships in the world which have survived to this day without significantly losing their original form. It includes warships, yachts, tall ships, and vessels recovered during archaeological excavations. It does not include reconstructions or replicas, partially complete wreckage, or ships which have been located but remain underwater. For example, the Mary Rose, whose remains consist only of a partial hull, is not included here. Vessels listed are sorted by date of launching as most accurately known.
  • 4.5K
  • 07 Nov 2022
Topic Review
Reusable Launch System
A reusable launch system is a launch system that allows for the reuse of some or all of the component stages. To date, several fully reusable suborbital systems and partially reusable orbital systems have been flown. The first reusable spacecraft to reach orbit was the Space Shuttle (in 1981), which failed to accomplish the intended goal of reducing launch costs to below those of expendable launch systems. During the 21st century, commercial interest in reusable launch systems has grown considerably, with several active launchers. SpaceX CEO Elon Musk has said that if one can figure out how to reuse rockets like airplanes then the cost of access to space will be reduced by as much as a factor of a hundred. SpaceX's Falcon 9 rocket has a reusable first stage and capsule (for Dragon flights) with an expendable second stage. SpaceX has been developing a reusable second stage since the late 2010s which, if successful, could make possible the first fully-reusable orbital launch vehicle during the 2020s. Virgin Galactic has flown reusable suborbital spaceplanes, and the suborbital Blue Origin New Shepard rocket has a recoverable boost stage and passenger capsule.
  • 4.4K
  • 12 Dec 2022
Topic Review
Bombardier CRJ200
The Bombardier CRJ100 and CRJ200 (formerly known as the Canadair CRJ100 and CRJ200) are a family of regional airliners designed and manufactured by Bombardier. The CRJ had the distinction of marking Canada's entry into the civil jet industry. It was based on the Canadair Challenger business jet. An initial effort to produce an enlarged 36-seat version of the aircraft, known as the Challenger 610E, was terminated during 1981. Shortly after Canadair's privatisation and sale to Bombardier, work on a stretched derivative was reinvigorated; during early 1989, the Canadair Regional Jet program was formally launched. On 10 May 1991, the first of three CRJ100 prototypes conducted its maiden flight. The type first entered service during the following year with its launch customer, Germany airline Lufthansa. The initial variant, the CRJ100, was soon joined by another model, designated as the CRJ200. It was largely identical to the CRJ100, except for the installation of more efficient turbofan engines, which gave the aircraft lower fuel consumption, increased cruise altitude and cruise speed. During the 1990s, various additional versions and models of the type were developed and put into service. During the late 1990s, a substantially enlarged derivative of the airliner, referred to as the CRJ700, was developed; it was soon joined by the even larger CRJ900 and CRJ1000. During 2006, production of both the CRJ100 and CRJ200 came to an end; the majority of produced airliners have remained in revenue service to date. Additionally, several airlines have modernised their fleets to support extended service.
  • 4.4K
  • 27 Oct 2022
Topic Review
Type 69 RPG
The Type 69 85mm rocket propelled grenade (RPG), made by Norinco, is a Chinese variant of the Soviet RPG-7. First introduced in 1972, the Type 69 is a common individual anti-tank weapon in service with the PLA. More advanced grenade rounds were developed in the 1980s and 1990s to meet the requirements of modern battlefields. Eventually, the aging Type 69 RPG family was replaced by modern anti-tank weapon systems developed by China such as Type 89 and Type 08.
  • 4.4K
  • 08 Nov 2022
Topic Review
Diamond DA42
The Diamond DA42 Twin Star is a four seat, twin engine, propeller-driven airplane developed and manufactured by Austrian company Diamond Aircraft Industries. It was Diamond's first twin engine design, as well as the first new European twin-engine aircraft in its category to be developed in over 25 years. In 2004, the DA42 became the first diesel-powered fixed-wing aircraft to perform a non-stop crossing of the North Atlantic. By 2012, the DA42 had become a key revenue generator for the company, having gained popularity with government and military operators in addition to the civil market that had suffered as a result of the Great Recession. Government customers have typically employed the type in the aerial surveillance role, which contributed towards the development of the Aeronautics Defense Dominator, a medium-altitude long-endurance (MALE) unmanned aerial vehicle (UAV), which had been derived from the DA42.
  • 4.4K
  • 21 Nov 2022
Topic Review
High-Speed Train Noise Control Methods
The sound of trains is considered a disturbance to most residents around the railroad and train passengers, and the sound generated by trains can interfere with sleep, life, and work. With increases in train speed, the main noise from high-speed trains has changed from rolling noise to aerodynamic noise, and the noise level and noise frequency range have also changed significantly. The current methods of noise reduction for trains are discussed.
  • 4.4K
  • 09 Aug 2022
Topic Review
F-X (Japan)
The F-X (unofficially called F-3) is a sixth-generation stealth fighter in development for the Japan Air Self-Defense Force (JASDF). It is Japan's first domestically developed stealth fighter jet and will replace the Mitsubishi F-2 by the mid–2030's. Its development is to also bolster the nation's defense industry and potentially enter the international arms market amid Japan's change in defense posture. The F-X has been nicknamed the "Godzilla" fighter owing to its large size, as well as a nod to the popular Kaiju.
  • 4.4K
  • 17 Oct 2022
Topic Review
Power-System Protection
Power-system protection is a branch of electrical power engineering that deals with the protection of electrical power systems from faults through the disconnection of faulted parts from the rest of the electrical network. The objective of a protection scheme is to keep the power system stable by isolating only the components that are under fault, whilst leaving as much of the network as possible still in operation. Thus, protection schemes must apply a very pragmatic and pessimistic approach to clearing system faults. The devices that are used to protect the power systems from faults are called protection devices.
  • 4.4K
  • 16 Nov 2022
Topic Review
Kepler (Spacecraft)
Kepler is a space observatory launched by NASA to discover Earth-size planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched on March 7, 2009, into an Earth-trailing heliocentric orbit. The principal investigator was William J. Borucki. Designed to survey a portion of our region of the Milky Way to discover Earth-size exoplanets in or near habitable zones and estimate how many of the billions of stars in the Milky Way have such planets, Kepler's sole scientific instrument is a photometer that continually monitors the brightness of approx 150,000 main sequence stars in a fixed field of view. These data are transmitted to Earth, then analyzed to detect periodic dimming caused by exoplanets that cross in front of their host star. Kepler is part of NASA's Discovery Program of relatively low-cost, focused primary science missions. The telescope's construction and initial operation were managed by NASA's Jet Propulsion Laboratory, with Ball Aerospace responsible for developing the Kepler flight system. The Ames Research Center is responsible for the ground system development, mission operations since December 2009, and scientific data analysis. The initial planned lifetime was 3.5 years, but greater-than-expected noise in the data, from both the stars and the spacecraft, meant additional time was needed to fulfill all mission goals. Initially, in 2012, the mission was expected to be extended until 2016, but on July 14, 2012, one of the spacecraft's four reaction wheels used for pointing the spacecraft stopped turning, and completing the mission would only be possible if all other reaction wheels remained reliable. Then, on May 11, 2013, a second reaction wheel failed, disabling the collection of science data and threatening the continuation of the mission. On August 15, 2013, NASA announced that they had given up trying to fix the two failed reaction wheels. This meant the current mission needed to be modified, but it did not necessarily mean the end of planet hunting. NASA had asked the space science community to propose alternative mission plans "potentially including an exoplanet search, using the remaining two good reaction wheels and thrusters". On November 18, 2013, the K2 "Second Light" proposal was reported. This would include utilizing the disabled Kepler in a way that could detect habitable planets around smaller, dimmer red dwarfs. On May 16, 2014, NASA announced the approval of the K2 extension. (As of January 2015), Kepler and its follow-up observations had found 1,013 confirmed exoplanets in about 440 star systems, along with a further 3,199 unconfirmed planet candidates.[upper-alpha 2] Four planets have been confirmed through Kepler's K2 mission. In November 2013, astronomers estimated, based on Kepler space mission data, that there could be as many as 40 billion rocky, Earth-size exoplanets orbiting in the habitable zones of Sun-like stars and red dwarfs within the Milky Way. It is estimated that 11 billion of these planets may be orbiting Sun-like stars. The nearest such planet may be 3.7 parsecs (12 ly) away, according to the scientists. On January 6, 2015, NASA announced the 1,000th confirmed exoplanet discovered by the Kepler Space Telescope. Four of the newly confirmed exoplanets were found to orbit within habitable zones of their related stars: three of the four, Kepler-438b, Kepler-442b and Kepler-452b, are almost Earth-size and likely rocky; the fourth, Kepler-440b, is a super-Earth. On May 10, 2016, NASA verified 1,284 new exoplanets found by Kepler, the single largest finding of planets to date. Kepler data has also helped scientists observe and understand supernovae; measurements were collected every half-hour so the light curves were especially useful for studying these types of astronomical events.
  • 4.3K
  • 20 Oct 2022
Topic Review
Cessna 210
The Cessna 210 Centurion is a six-seat, high-performance, retractable-gear, single-engine, high-wing general aviation aircraft which was first flown in January 1957 and produced by Cessna until 1986.
  • 4.3K
  • 11 Oct 2022
Topic Review
Mercedes-Benz GLC-Class
The Mercedes-Benz GLC-Class (X253/C253) is a compact luxury crossover SUV introduced in 2015 for the 2016 model year that replaces the GLK-Class. According to Mercedes-Benz, it is the SUV equivalent to the C-Class. Although officially considered compact, it is considered mid-size in the US market. Under the vehicle naming scheme maintained by Mercedes-Benz, SUVs use the base name "GL", followed by the model's placement in Mercedes-Benz hierarchy. The "G" is for Geländewagen (German for off-road vehicle) and alludes to the long-running G-Class. This is followed by the letter "L" that acts as a linkage with the letter "C" to signify that the vehicle is a SUV equivalent to the C-Class.
  • 4.3K
  • 21 Oct 2022
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