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Topic Review
Carbon-Based Quantum Dots for Supercapacitors
Carbon-based Quantum dots (C-QDs) are carbon-based materials that experience the quantum confinement effect, which results in superior optoelectronic properties. In recent years, C-QDs have attracted attention significantly and have shown great application potential as a high-performance supercapacitor device. C-QDs (either as a bare electrode or composite) give a new way to boost supercapacitor performances in higher specific capacitance, high energy density, and good durability. This review comprehensively summarizes the up-to-date progress in C-QD applications either in a bare condition or as a composite with other materials for supercapacitors. The current state of the three distinct C-QD families used for supercapacitors including carbon quantum dots, carbon dots, and graphene quantum dots is highlighted. 
  • 4.8K
  • 28 Sep 2021
Topic Review
South Korean Transitional Periods from Imitation to Innovation
The technology transfer and development model of South Korea is unique. After other countries refused to license and transfer modern technologies to this country, Korea resorted to its national research system to add innovative content to its imitative products. 
  • 4.7K
  • 23 Mar 2022
Topic Review
Boeing 787 Dreamliner Battery Problems
In 2013, the second year of service for the Boeing 787 Dreamliner, a widebody jet airliner and several aircraft suffered from electrical system problems stemming from its lithium-ion batteries. Incidents included an electrical fire aboard an All Nippon Airways 787 and a similar fire found by maintenance workers on a parked Japan Airlines 787 at Boston's Logan International Airport. The United States Federal Aviation Administration (FAA) ordered a review into the design and manufacture of the Boeing 787 Dreamliner, followed by a full grounding of the entire Boeing 787 fleet, the first such grounding since that of the McDonnell Douglas DC-10 in 1979. The plane has had two major battery thermal runaway events in 52,000 flight hours, which was substantially less than the 10 million flight hours predicted by Boeing, neither of which were contained safely. The National Transportation Safety Board (NTSB) released a report on December 1, 2014, and assigned blame to several groups:
  • 4.7K
  • 14 Nov 2022
Biography
Firouz Naderi
Firouz Michael Naderi (Persian: فیروز نادری‎: Fīrouz Nāderi; born 1946) is an Iranian scientist who spent more than 30 years in various technical and executive positions at NASA's Jet Propulsion Laboratory (JPL) where he contributed to some of America's most iconic robotic space missions. He retired from NASA in 2016 and currently is a management consultant, an advisor to early-st
  • 4.7K
  • 15 Nov 2022
Topic Review
Cooper (Profession)
A cooper is a person trained to make wooden casks, barrels, vats, buckets, tubs, troughs and other similar containers from timber staves that were usually heated or steamed to make them pliable. Journeymen coopers also traditionally made wooden implements, such as rakes and wooden-bladed shovels. In addition to wood, other materials, such as iron, were used in the manufacturing process. The trade is the origin of the surname Cooper.
  • 4.7K
  • 17 Oct 2022
Topic Review
An Informative Lithium-Ion Battery Datasheet
Lithium-ion battery datasheets, also known as specification sheets, are documents that battery manufacturers provide to define the battery’s function, operational limit, performance, reliability, safety, cautions, prohibitions, and warranty. A datasheet lists information about the product for both informational and advertising purposes. Product manufacturers and customers rely on the datasheets for battery selection and battery management. 
  • 4.7K
  • 29 Sep 2021
Topic Review
Ordnance QF 6-pounder
The Ordnance Quick-Firing 6-pounder 7 cwt,[note 1] or just 6-pounder, was a British 57 mm gun, serving during the Second World War as a primary anti-tank gun of both the British and United States Army (as the 57 mm Gun M1). It was also used as the main armament for a number of armoured fighting vehicles. Although designed before the start of the war, it did not reach service until the North African Campaign in April 1942. There, it replaced the 2-pounder as an anti-tank gun, allowing the 25-pounder gun-howitzer to revert to its intended artillery role.
  • 4.6K
  • 03 Nov 2022
Topic Review
Stress and Strain Induced Transformations
Displacive stress and strain induced transformations are those transformations that occur when the formation of martensite or bainitic ferrite is promoted by the application of stress or strain. These transformations have been shown to be one of the mechanisms by which the mechanical properties of a microstructure can be improved, as they lead to a better ductility and strength by the transformation induced plasticity effect. 
  • 4.6K
  • 08 Mar 2021
Topic Review
Control Rod
Control rods are used in nuclear reactors to control the rate of fission of the nuclear fuel – uranium or plutonium. Their compositions include chemical elements such as boron, cadmium, silver, hafnium, or indium, that are capable of absorbing many neutrons without themselves fissioning. These elements have different neutron capture cross sections for neutrons of various energies. Boiling water reactors (BWR), pressurized water reactors (PWR), and heavy-water reactors (HWR) operate with thermal neutrons, while breeder reactors operate with fast neutrons. Each reactor design can use different control rod materials based on the energy spectrum of its neutrons.
  • 4.6K
  • 11 Nov 2022
Topic Review
Radeon HD 7000 Series
The Radeon HD 7000 Series, based on "Southern Islands", is further products series in the family of Radeon GPUs developed by AMD. AMD builds Southern Islands series graphics chips based on the 28 nm manufacturing process at TSMC. The primary competitor of Southern Islands, Nvidia's GeForce 600 Series (also manufactured at TSMC), also shipped during Q1 2012, largely due to the immaturity of the 28 nm process.
  • 4.6K
  • 08 Nov 2022
Topic Review
AI-Based and Big Data Analytics on Urban Planning
In order to enable a holistic approach to design and planning, there is a need to integrate those data sources and combine them with other more traditional methods of urban assessment. At the same time, there are still various concerns about big data analytics based on AI-related tools connected, for example, with the accessibility to and accuracy of big data, as well as the limitations of different types of AI-based tools which do not permit this kind of analytics to fully replace traditional urban planning analyses. In terms of technological change, the application of big data in design and planning may greatly support traditional planning methods and provide conditions for innovation; however, due to its limitations, it can only enrich but in no way replace traditional urban studies.
  • 4.6K
  • 03 Dec 2021
Topic Review
Dugout Canoe
A dugout canoe or simply dugout is a boat made from a hollowed tree. Other names for this type of boat are logboat and monoxylon. Monoxylon (μονόξυλον) (pl: monoxyla) is Greek -- mono- (single) + ξύλον xylon (tree) -- and is mostly used in classic Greek texts. In German, they are called Einbaum ("one tree" in English). Some, but not all, pirogues are also constructed in this manner. Dugouts are the oldest boat type archaeologists have found, dating back about 8,000 years to the Neolithic Stone Age. This is probably because they are made of massive pieces of wood, which tend to preserve better than, e.g., bark canoes. Along with bark canoe and hide kayak, dugout boats were also used by indigenous peoples of the Americas.
  • 4.6K
  • 25 Oct 2022
Topic Review
Indian Regional Navigation Satellite System
The Indian Regional Navigation Satellite System (IRNSS), with an operational name of NAVIC (acronym for NAVigation with Indian Constellation; also, nāvik 'sailor' or 'navigator' in Sanskrit, Hindi, and many other Indian languages), is an autonomous regional satellite navigation system that provides accurate real-time positioning and timing services. It covers India and a region extending 1,500 km (930 mi) around it, with plans for further extension. An extended service area lies between the primary service area and a rectangle area enclosed by the 30th parallel south to the 50th parallel north and the 30th meridian east to the 130th meridian east, 1,500–6,000 km (930–3,730 mi) beyond borders. The system currently consists of a constellation of seven satellites, with two additional satellites on ground as stand-by. The constellation is in orbit as of 2018, and the system was expected to be operational from early 2018 after a system check. NAVIC will provide two levels of service, the "standard positioning service", which will be open for civilian use, and a "restricted service" (an encrypted one) for authorised users (including the military). NAVIC is planned to become available for civilian use in the first half of 2020. There are plans to expand the NAVIC system by increasing its constellation size from 7 to 11.
  • 4.5K
  • 12 Oct 2022
Topic Review
Compaq Presario 2200
The Compaq Presario 2200 is a small form factor desktop PC produced by Compaq from 1997 to 1998. It was produced as a slim, small form factor machine mainly intended for budget-minded consumers. When launched, it had 16 MB of EDO DRAM that was expandable up to 80 MB and a Cyrix MediaGXi microprocessor, clocking at 180 MHz. It did not include an Ethernet port; however, the modem can be swapped out for a compatible 8-bit ISA Ethernet card to allow the computer to be connected to the Internet or a LAN network. There are no USB ports on the computer, even though the small metal flap might suggest that Compaq considered installing USB ports during the time the computer was developed. This computer model is not to be confused with the newer Compaq Presario 2200 laptop computer.
  • 4.5K
  • 09 Nov 2022
Topic Review
Reclaimed Water
Reclaimed or recycled water (also called wastewater reuse or water reclamation) is the process of converting wastewater into water that can be reused for other purposes. Reuse may include irrigation of gardens and agricultural fields or replenishing surface water and groundwater (i.e., groundwater recharge). Reused water may also be directed toward fulfilling certain needs in residences (e.g. toilet flushing), businesses, and industry, and could even be treated to reach drinking water standards. This last option is called either "direct potable reuse" or "indirect potable" reuse, depending on the approach used. Reclaiming water for reuse applications instead of using freshwater supplies can be a water-saving measure. When used water is eventually discharged back into natural water sources, it can still have benefits to ecosystems, improving streamflow, nourishing plant life and recharging aquifers, as part of the natural water cycle. Wastewater reuse is a long-established practice used for irrigation, especially in arid countries. Reusing wastewater as part of sustainable water management allows water to remain as an alternative water source for human activities. This can reduce scarcity and alleviate pressures on groundwater and other natural water bodies.
  • 4.5K
  • 24 Oct 2022
Topic Review
Biomimicry
Biomimicry can be defined as the branch of science for developing technology by mimicking nature, where forms and structures of creatures are the basic sources of inspiration to come up with optimized design solutions.
  • 4.5K
  • 12 Mar 2021
Topic Review
Surfactants versus Biosurfactants
Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis.
  • 4.5K
  • 14 Mar 2021
Topic Review
Lockheed Martin Compact Fusion Reactor
The Lockheed Martin Compact Fusion Reactor (CFR) is a proposed nuclear fusion reactor project at Lockheed Martin’s Skunk Works. Its high-beta configuration, which implies that the ratio of plasma pressure to magnetic pressure is greater than or equal to 1 (compared to tokamak designs' 0.05), allows a compact fusion reactor (CFR) design and expedited development. The CFR chief designer and technical team lead, Thomas McGuire studied fusion as a source of space propulsion in response to a NASA desire to improve travel times to Mars.
  • 4.5K
  • 17 Oct 2022
Biography
Robert Kearns
Robert William Kearns PhD (March 10, 1927 – February 9, 2005) was an American engineer, educator and inventor who invented the intermittent windshield wiper systems used on most automobiles from 1969 to the present. His first patent for the invention was filed on December 1, 1964. Kearns won one of the best known patent infringement cases against Ford Motor Company (1978–1990) and a case a
  • 4.4K
  • 23 Nov 2022
Topic Review
SpaceX Dragon
Dragon, also known as Dragon 1 or Cargo Dragon, was a class of partially reusable cargo spacecraft developed by SpaceX, an American private space transportation company. Dragon was launched into orbit by the company's Falcon 9 launch vehicle to resupply the International Space Station (ISS). During its maiden flight in December 2010, Dragon became the first commercially built and operated spacecraft to be recovered successfully from orbit. On 25 May 2012, a cargo variant of Dragon became the first commercial spacecraft to successfully rendezvous with and attach to the ISS. SpaceX is contracted to deliver cargo to the ISS under NASA's Commercial Resupply Services program, and Dragon began regular cargo flights in October 2012. With the Dragon spacecraft and the Orbital ATK Cygnus, NASA seeks to increase its partnerships with domestic commercial aviation and aeronautics industry. On 3 June 2017, the C106 capsule, largely assembled from previously flown components from the CRS-4 mission in September 2014, was launched again for the first time on CRS-11, with the hull, structural elements, thrusters, harnesses, propellant tanks, plumbing and many of the avionics reused, while the heat shield, batteries and components exposed to sea water upon splashdown for recovery were replaced. SpaceX developed a second version called Dragon 2, which is capable of transporting humans. Flight testing was completed in 2019, after a delay caused by a test pad anomaly in April 2019, which resulted in the loss of a Dragon 2 capsule. The first flight of astronauts on Dragon 2 occurred on the Crew Dragon Demo-2 mission in May 2020. The last flight of the first version of the Dragon spacecraft (Dragon 1) launched 7 March 2020 (UTC); it was a cargo resupply mission (CRS-20) to International Space Station (ISS). This mission was the last mission of SpaceX of the first Commercial Resupply Services (CRS-1) program, and marked the retirement of the Dragon 1 fleet. Further SpaceX commercial resupply flights to ISS under the second Commercial Resupply Services (CRS-2) program use the cargo-carrying variant of the SpaceX Dragon 2 spacecraft.
  • 4.4K
  • 12 Oct 2022
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