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Topic Review
Convair B-36 Variants
The development of the Convair B-36 strategic bomber began in 1941 with the XB-36, which was intended to meet the strategic needs of the US Army Air Forces , and later of the United States Air Force with its Strategic Air Command. In 1948, the B-36 become a mainstay of the American nuclear deterrent. It underwent a number of design changes before being withdrawn from service in 1959. It was also well suited to high altitude very long range reconnaissance missions, and several alterations were made with this mission profile in mind.
  • 1.0K
  • 31 Oct 2022
Topic Review
Terraforming in Popular Culture
Terraforming is well represented in contemporary literature, usually in the form of science fiction, as well as in popular culture. While many stories involving interstellar travel feature planets already suited to habitation by humans and supporting their own indigenous life, some authors prefer to address the unlikeliness of such a concept by instead detailing the means by which humans have converted inhospitable worlds to ones capable of supporting life through artificial means.
  • 1.0K
  • 15 Nov 2022
Topic Review
Siding
Siding or wall cladding is the protective material attached to the exterior side of a wall of a house or other building. Along with the roof, it forms the first line of defense against the elements, most importantly sun, rain/snow, heat and cold, thus creating a stable, more comfortable environment on the interior side. The siding material and style also can enhance or detract from the building's beauty. There is a wide and expanding variety of materials to side with, both natural and artificial, each with its own benefits and drawbacks. Masonry walls as such do not require siding, but any wall can be sided. Walls that are internally framed, whether with wood, or steel I-beams, however, must always be sided. Most siding consists of pieces of weather-resistant material that are smaller than the wall they cover, to allow for expansion and contraction of the materials due to moisture and temperature changes. There are various styles of joining the pieces, from board and batton, where the butt joints between panels is covered with a thin strip (usually 1 to 2 inches wide) of wood, to a variety of clapboard, also called lap siding, in which planks are laid horizontally across the wall starting from the bottom, and building up, the board below overlapped by the board above it. These techniques of joinery are designed to prevent water from entering the walls. Siding that does not consist of pieces joined together would include stucco, which is widely used in the Southwest. It is a plaster-like siding and is applied over a lattice, just like plaster. However, because of the lack of joints, it eventually cracks and is susceptible to water damage. Rainscreen construction is used to improve siding's ability to keep walls dry.
  • 1.0K
  • 17 Oct 2022
Topic Review
F9R Dev1
Grasshopper and the Falcon 9 Reusable Development Vehicles (F9R Dev) were experimental flight test reusable rockets that performed vertical takeoffs and landings. The project was privately funded by SpaceX, with no funds provided by any government until later on. Two prototypes were built, and both were launched from the ground. Grasshopper was announced in 2011 and began low-altitude, low-velocity hover/landing testing in 2012. The initial Grasshopper test vehicle was 106 ft (32 m) tall and made eight successful test flights in 2012 and 2013 before being retired. A second Grasshopper-class prototype was the larger and more capable Falcon 9 Reusable Development Vehicle (F9R Dev, also known as F9R Dev1) based on the Falcon 9 v1.1 launch vehicle. It was tested at higher altitudes and was capable of much higher velocity but was never tested at high velocity. The F9R Dev1 vehicle was built in 2013–2014 and made its first low-altitude flight test on 17 April 2014; it was lost during a three-engine test at the McGregor test site on 22 August 2014, which ended the low-velocity test program. Further expansion of the flight test envelope for the reusable rocket was moved to descending Falcon 9 boosters that had been used on orbital flight trajectories on commercial orbital flights of the Falcon 9. The Grasshopper and F9R Dev tests were fundamental to the development of the reusable Falcon 9 and Falcon Heavy rockets, which require vertical landings of the near-empty Falcon 9 and Falcon Heavy first-stage booster tanks and engine assemblies. The Grasshopper and the F9R Dev tests led into a series of high-altitude, high-speed controlled-descent tests of post-mission (spent) Falcon 9 booster stages that accompanied the commercial Falcon 9 missions since September 2013. The latter eventually resulted in the first successful booster landing on 21 December 2015.
  • 1.0K
  • 14 Nov 2022
Topic Review
CajunBot
CajunBot refers to the autonomous ground vehicles developed by the University of Louisiana at Lafayette for the DARPA Grand Challenges. CajunBot was featured on CNN and on the Discovery Channel science series Robocars. CajunBot's custom AGV software, CBSystem, has artificial intelligence path planning capabilities, as well as visualization and simulation components. The hardware repertoire of CajunBot includes a high grade GPS/INS positioning unit to navigate a designated route while detecting and avoiding obstacles using LIDAR laser-ranging units.
  • 1.0K
  • 17 Oct 2022
Topic Review
Canadair CL-84
The Canadair CL-84 "Dynavert", designated by the Canadian Forces as the CX-131, was a V/STOL turbine tiltwing monoplane designed and manufactured by Canadair between 1964 and 1972. Only four of these experimental aircraft were built with three entering flight testing. Two of the CL-84s crashed due to mechanical failures, with no fatalities occurring in either of the accidents. Despite the fact that the CL-84 was successful in the experimental and operational trials carried out between 1972 and 1974 however, none of the prospective customers placed any orders for the type.
  • 999
  • 31 Oct 2022
Topic Review
Stability Modelling of mRNA Vaccine Quality
The vaccine distribution chains in several low- and middle-income countries are not adequate to facilitate the rapid delivery of high volumes of thermosensitive COVID-19 mRNA vaccines at the required low and ultra-low temperatures. COVID-19 mRNA vaccines are currently distributed along with temperature monitoring devices to track and identify deviations from predefined conditions throughout the distribution chain. These temperature readings can feed into computational models to quantify mRNA vaccine critical quality attributes (CQAs) and the remaining vaccine shelf life more accurately. Here, a kinetic modelling approach is proposed to quantify the stability-related CQAs and the remaining shelf life of mRNA vaccines. The CQA and shelf-life values can be computed based on the conditions under which the vaccines have been distributed from the manufacturing facilities via the distribution network to the vaccination centres.
  • 997
  • 28 Feb 2022
Topic Review
Mindwipe (Transformers)
Mindwipe is the name of two fictional characters in the Transformers toy line and fictional series by Hasbro. Both are Decepticons.
  • 994
  • 02 Nov 2022
Topic Review
Digital Twin
A digital twin is a virtual model of a physical object, a process, a machine, or their component that can be converted into an inherently complex mathematical model. The term of digital twin can be understood in correspondence to a digital shadow and a digital model. A digital twin is based on automatic data flow in contrast to the digital shadow which can work based either on manual or automatic data flow. Whereas a digital model can operate with manual data flow solely. It should be underlined here that a digital model and a physical object are not interconnected by any automatic data exchange. Consequently, a digital shadow is defined as a digital version of an object (a process, a machine, or their component; further mentioned as an object) that is characterized by a one-direction impact between a physical and digital object. A change in any state of a physical object is reflected in a digital model of a physical object, while the reverse situation does not occur. In the case of a digital twin, an impact between a physical object and its digital reflection is mutual. Once a change in any state in a physical object occurs, it automatically leads to a change in a digital object. The opposite interconnection occurs as well. A digital twin is characterized by the following features: interoperability (objects, machines, and people need to be able to communicate with each other via the Internet and in particular IoT in order to enable mutual interconnection of a digital twin with a physical object), virtualization (everything physical within a particular object, process or facility must have a virtual equivalent), autonomy (understood through the mutual communication), working in real-time (a digital twin and a corresponding physical object must operate in real-time, aggregate collected data, analyze them and make decisions in accordance with new arrangements). Currently, many machines and products within the manufacturing industry have sufficient prerequisites to use digital twins, for example owing to the connection of production machines to the IT systems. Alongside means of automation and data exchange in manufacturing technologies including the Internet of Things, cloud computing, cyber-physical systems, big data and analytics, simulation and augmented reality, this technology fits into the concept of innovations within Industry 4.0.   The terms of a digital twin, digital shadow, and digital model were defined based on the following references: 1.       Fuller, A.; Fan, Z.; Day, C.; Barlow, C. Digital Twin: Enabling Technologies, Challenges and Open Research. IEEE Access 2020, 8, 108952–108971, doi:10.1109/ACCESS.2020.2998358. 2.       Kosacka-Olejnik, M.; Kostrzewski, M.; Marczewska, M.; Mrówczyńska, B.; Pawlewski, P. How Digital Twin Concept Supports Internal Transport Systems?—Literature Review. Energies 2021, 14, 4919. https://doi.org/10.3390/en14164919 3.       Muhuri, P.K.; Shukla, A.K.; Abraham, A. Industry 4.0: A Bibliometric Analysis and Detailed Overview. Engineering Applications of Artificial Intelligence 2019, 78, 218–235, doi:10.1016/j.engappai.2018.11.007. 4.       Tay, S.I.; Lee, T.C.; Hamid, N.Z.A.; Ahmad, A.N.A. An Overview of Industry 4.0: Definition, Components, and Government Initiatives. Journal of Advanced Research in Dynamical and Control Systems 2018, 10, 1379–1387. 5.       Trotta, D.; Garengo, P. Industry 4.0 Key Research Topics: A Bibliometric Review. In Proceedings of the 2018 7th International Conference on Industrial Technology and Management (ICITM); IEEE: Oxford, United Kingdom, March 2018; pp. 113–117.
  • 988
  • 15 Sep 2022
Topic Review
Darkwing (Transformers)
Darkwing (sometimes called Darkwind or Blackwing) is a fictional character from the various Transformers series. He is a Decepticon jet.
  • 983
  • 17 Oct 2022
Topic Review
CANT Z.506
The CANT Z.506 Airone (Italian: Heron) was a triple-engine floatplane produced by CANT from 1935. It served as a transport and postal aircraft with the Italian airline "Ala Littoria". It established 10 world records in 1936 and another 10 in 1937. During World War II it was used as a reconnaissance aircraft, bomber and air-sea rescue plane, by the Italian Regia Aeronautica and Regia Marina, Aeronautica Cobelligerante del Sud, Aeronautica Nazionale Repubblicana and the Luftwaffe. The military version revealed itself to be one of the best floatplanes ever built. Despite its wooden structure it was able to operate in very rough seas. A number of Z.506S air-sea rescue aircraft remained in service until 1959.
  • 983
  • 31 Oct 2022
Topic Review
Micromobility in Urban Transportation
Micromobility is a novel approach to urban transportation that provides options for short-distance travel, such as first- and last-kilometer trips. Its primary attraction is the provision of an on-demand, affordable, eco-friendly, and adaptable transportation option, reducing reliance on private vehicles for short distances.
  • 981
  • 04 Jan 2024
Topic Review
Nuclear-Renewable Hybrid Energy System for Fast Charging Stations
The transportation sector is a significant source of greenhouse gas emissions. Electric vehicles (EVs) have gained popularity as a solution to reduce emissions, but the high load of charging stations poses a challenge to the power grid. Nuclear-Renewable Hybrid Energy Systems (N-RHES) present a promising alternative to support fast charging stations, reduce grid dependency, and decrease emissions. However, the intermittent problem of renewable energy sources (RESs) limits their application, and the synergies among different technologies have not been fully exploited. The researchers propose a predictive and adaptive control strategy to optimize the energy management of N-RHES for fast charging stations, considering the integration of nuclear, photovoltaics, and wind turbine energy with a hydrogen storage fuel cell system. The proposed dynamic model of a fast-charging station predicts electricity consumption behavior during charging processes, generating probabilistic forecasting of electricity consumption time-series profiling. Key performance indicators and sensitivity analyses illustrate the practicability of the suggested system, which offers a comprehensive solution to provide reliable, sustainable, and low-emission energy to fast-charging stations while reducing emissions and dependency on the power grid.
  • 977
  • 26 May 2023
Topic Review
Mast Aft Rig
A mast aft rig, alternately referred to as aft-mast rig, is a sailboat sail-plan that uses a single mast set in the aft half of the hull. The mast supports fore-sails that may consist of a single jib multiple staysails, or a crab claw sail. The mainsail is either small or completely absent. Mast aft rigs are uncommon, but are found on a few custom, and production sailboats.
  • 976
  • 01 Nov 2022
Topic Review
Drone Applications Fighting COVID-19
The non-military use of drones is becoming more widespread, which the media is now increasingly reporting. Drone applications fighting Covid-19 can be divided into different types of groups: surveillance of an area with a visual camera, detection of fever-infected people with a thermal camera, communication with an on-board installed loudspeaker or QR code flag and three different logistic tasks such as transportation of essentials, health products and disinfectants.   
  • 967
  • 12 Jan 2022
Topic Review
Intrastate Airline
Intrastate airlines in the U.S. are defined as air carriers operating inside of one individual state and thus not flying across state lines. Larger intrastate airlines in the U.S. that operated mainline turboprop and/or jet aircraft were created as a result of past federal airline regulations as passenger air carriers that only flew intrastate service were not regulated by the federal government but were instead primarily regulated by the respective state governments in their home states. For example, Pacific Southwest Airlines (PSA) and Air California were both regulated by the California Public Utilities Commission (CPUC) prior to the federal Airline Deregulation Act of 1978. Intrastate air carriers primarily operated in the United States but also elsewhere globally. In the U.S., California, Florida, Hawaii and Texas had scheduled jet passenger service operated by intrastate air carriers in the past.
  • 967
  • 24 Oct 2022
Topic Review
World Bicycle Relief
World Bicycle Relief is an international, non-profit organization based in Chicago, IL that specializes in large-scale, comprehensive bicycle distribution programs to aid poverty relief in developing countries around the world. Their programs focus primarily on education, economic development, and health care. As of February 2020, World Bicycle Relief has distributed 500,000 bicycles in 21 countries and trained more than 2,300 bicycle mechanics in the developing world. Within their largest program, the Bicycles For Educational Empowerment program, nearly 70 percent of the student bicycles are designated for girl students.
  • 960
  • 14 Nov 2022
Topic Review
NUAA UAV
NUAA UAVs are Chinese UAVs developed by Nanjing University of Aeronautics and Astronautics (NUAA), and most of which are experimental UAV, but some of which have entered limited service in China.
  • 960
  • 19 Oct 2022
Topic Review
Holomorphic Embedding Load Flow Method
The Holomorphic Embedding Load-flow Method (HELM) is a solution method for the power flow equations of electrical power systems. Its main features are that it is direct (that is, non-iterative) and that it mathematically guarantees a consistent selection of the correct operative branch of the multivalued problem, also signalling the condition of voltage collapse when there is no solution. These properties are relevant not only for the reliability of existing off-line and real-time applications, but also because they enable new types of analytical tools that would be impossible to build with existing iterative load flow methods (due to their convergence problems). An example of this would be decision-support tools providing validated action plans in real time. The HELM load flow algorithm was invented by Antonio Trias and has been granted two US Patents. A detailed description was presented at the 2012 IEEE PES General Meeting and subsequently published. The method is founded on advanced concepts and results from complex analysis, such as holomorphicity, the theory of algebraic curves, and analytic continuation. However, the numerical implementation is rather straightforward as it uses standard linear algebra and the Padé approximation. Additionally, since the limiting part of the computation is the factorization of the admittance matrix and this is done only once, its performance is competitive with established fast-decoupled loadflows. The method is currently implemented into industrial-strength real-time and off-line packaged EMS applications.
  • 957
  • 25 Nov 2022
Topic Review
Soil Compaction
In geotechnical engineering, soil compaction is the process in which a stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water (or other liquid) being displaced from between the soil grains, then consolidation, not compaction, has occurred. Normally, compaction is the result of heavy machinery compressing the soil, but it can also occur due to the passage of (e.g.) animal feet. In soil science and agronomy, soil compaction is usually a combination of both engineering compaction and consolidation, so may occur due to a lack of water in the soil, the applied stress being internal suction due to water evaporation as well as due to passage of animal feet. Affected soils become less able to absorb rainfall, thus increasing runoff and erosion. Plants have difficulty in compacted soil because the mineral grains are pressed together, leaving little space for air and water, which are essential for root growth. Burrowing animals also find it a hostile environment, because the denser soil is more difficult to penetrate. The ability of a soil to recover from this type of compaction depends on climate, mineralogy and fauna. Soils with high shrink-swell capacity, such as vertisols, recover quickly from compaction where moisture conditions are variable (dry spells shrink the soil, causing it to crack). But clays which do not crack as they dry cannot recover from compaction on their own unless they host ground-dwelling animals such as earthworms — the Cecil soil series is an example.
  • 955
  • 14 Oct 2022
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