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Topic Review
Pepper-Box
The pepper-box revolver or simply pepperbox (also "pepper-pot", from its resemblance to the household pepper shakers) is a multiple-barrel firearm, mostly in the form of a handgun, that has three or more gun barrels in a coaxially revolving mechanism. Each barrel holds a single shot, and the shooter can manually rotate the whole barrel assembly to sequentially index each barrel into alignment with the lock/hammer, similar to operating a revolver cylinder. Pepperbox guns have existed for all action and ammunition systems: matchlock, wheellock, flintlock, snaplock, caplock, pinfire, rimfire and centerfire. While they are usually sidearms, a few long guns were also made. For example, Samuel Colt owned a three-barrel pepperbox matchlock musket from British India, and an eight-barrel pepperbox shotgun was designed in 1967 but never went into production.
  • 951
  • 09 Nov 2022
Topic Review
Sod Roof
A sod roof, or turf roof, is a traditional Scandinavian type of green roof covered with sod on top of several layers of birch bark on gently sloping wooden roof boards. Until the late 19th century, it was the most common roof on rural log houses in Norway and large parts of the rest of Scandinavia. Its distribution roughly corresponds to the distribution of the log building technique in the vernacular architecture of Finland and the Scandinavian peninsula. The load of approximately 250 kg per m² of a sod roof is an advantage because it helps to compress the logs and make the walls more draught-proof. In winter the total load may well increase to 400 or 500 kg per m² because of snow. Sod is also a reasonably efficient insulator in a cold climate. The birch bark underneath ensures that the roof will be waterproof. The term ‘sod roof’ is somewhat misleading, as the active, water-tight element of the roof is birch bark. The main purpose of the sod is to hold the birch bark in place. The roof might just as well have been called a "birch bark roof", but its grassy outward appearance is the reason for its name in Scandinavian languages: Norwegian and Swedish torvtak, Icelandic torfþak. A sod roof is well suited to the dynamics of a barter economy because the materials are ubiquitous and cost nothing, although the work is labour-intensive. However, a typical household in the era that sod roofs were most common would usually possess a lot of manpower, and neighbours would typically be invited to take part in the roofing party, similar to a barn raising in the United States . The Norwegian term dugnad denotes an established custom in rural communities, where large undertakings were accomplished with help from neighbours.
  • 950
  • 29 Sep 2022
Topic Review
Metacognition
Metacognition is an awareness of one's thought processes and an understanding of the patterns behind them. The term comes from the root word meta, meaning "beyond", or "on top of". Metacognition can take many forms, such as reflecting on one's ways of thinking and knowing when and how to use particular strategies for problem-solving. There are generally two components of metacognition: (1) knowledge about cognition and (2) regulation of cognition. Metamemory, defined as knowing about memory and mnemonic strategies, is an especially important form of metacognition. Academic research on metacognitive processing across cultures is in the early stages, but there are indications that further work may provide better outcomes in cross-cultural learning between teachers and students. Writings on metacognition date back at least as far as two works by the Greek philosopher Aristotle (384–322 BC): On the Soul and the Parva Naturalia.
  • 947
  • 14 Nov 2022
Topic Review
List of Intel Pentium M Microprocessors
The Pentium M brand refers to single-core 32-bit mobile CPUs codenamed Banias and Dothan, and targeted at the consumer market of mobile computers.
  • 944
  • 19 Oct 2022
Topic Review
Endocrine-Disrupting Compounds
The continual detection of endocrine-disrupting chemicals (EDCs) (ng/L or µg/L) in water and wastewater has attracted critical concerns among the regulatory authorities and general public, due to its associated public health, ecological risks, and a threat to global water quality. Presently, there is a lack of stringent discharge standards regulating the emerging multiclass contaminants to obviate its possible undesirable impacts.
  • 942
  • 18 Feb 2021
Biography
Otto Schmitt
Otto Herbert Schmitt (April 6, 1913 – January 6, 1998) was an United States inventor, engineer, and biophysicist known for his scientific contributions to biophysics and for establishing the field of biomedical engineering. Schmitt also coined the term biomimetics and invented the Schmitt trigger, the cathode follower, the differential amplifier, and the chopper-stabilized amplifier.[1] He wa
  • 942
  • 26 Dec 2022
Topic Review
Open BOK Context
A Body of Knowledge (BOK) is a concept used to represent concepts, terms, and activities that make up a professional domain. In addition, an Open BOK is necessary because it allows us to develop the abilities and talents of professionals in different Knowledge Areas (KAs).
  • 939
  • 02 Nov 2020
Topic Review
Shooting Star (Spacecraft)
The Shooting Star is an expendable American cargo spacecraft (transport vehicle) developed by Sierra Nevada Corporation as part of the Dream Chaser Launch System. It attaches to the back of Dream Chaser® spaceplane serving as a Service Module and holding up to 4,536 kg (10,000 lb) of supplies, cargo and experiments for the International Space Station. It is launched by ULA's Vulcan rocket and is designed to transport supplies to the International Space Station (ISS) and return items to Earth. Shooting Star can support three unpressurized payloads weighing up to 500 kg (1,100 lb) each or one payload weighing as much as 1,500 kg (3,300 lb). Once the module is at the station, the Canadarm2 robotic arm would unload the externally attached payload and install it on the station's exterior. The Shooting Star module is versatile, supplying power and ECLSS for the Dream Chaser system. It can be customized for special mission needs, such as autonomous docking to ISS instead of berthing. Upon re-entry into Earth’s atmosphere, it also performs disposal of cargo from the International Space Station.
  • 938
  • 27 Oct 2022
Topic Review
Active Design
Active Design is a set of building and planning principles that promote physical activity. Active design in a building, landscape or city design integrates physical activity into the occupants' everyday routines, such as walking to the store or making a photocopy. Active design involves urban planners, architects, transportation engineers, public health professionals, community leaders and other professionals in building places that encourage physical activity as an integral part of life. While not an inherent part of active design, most designers employing "active design" are also concerned with the productive life of their buildings and their building's ecological footprint.
  • 930
  • 21 Oct 2022
Topic Review
Microwave Kinetic Induction Detectors
Microwave Kinetic Inductance Detectors (MKIDs) are superconducting low-temperature detectors for photons or particles. They are based on the change of resonant frequency of superconducting LC resonators by Cooper pair breaking and their unrivalled scalability makes them one of the most promising novel low temperature detector technologies. 
  • 919
  • 29 Mar 2021
Topic Review
Substrate Materials of Microfluidic-Microwave Devices
The area of microfluidic devices with microwave components is constantly increasing. There are four main types of materials, that can act as a substrate for the microwave-microfluidic systems—epoxy-glass laminates, polymer materials, glass/silicon substrates, and Low-Temperature Cofired Ceramics (LTCCs). The entry describes and compares briefly all selected materials.
  • 917
  • 22 Apr 2021
Topic Review
Burt’s Solar Compass
Burt's solar compass is a surveying instrument that makes use of the sun's direction instead of magnetism. William Austin Burt invented his solar compass in 1835. It is a device which allows a person to find the north direction from the position of a shadow. The reason for this instrument was to get away from the erratic readings of a normal magnetized compass when in a local land territory of high iron ore content. The instrument was found to be so accurate that it was the choice of the United States government when surveying public lands, state boundaries, and railroad routes. It won awards from various organizations for its technology. It was used by surveyors from the nineteenth century into the twentieth century.
  • 917
  • 19 Oct 2022
Topic Review
DAvE (Infineon)
DAVE (Infineon) Digital Application Virtual Engineer (DAVE), is a C/C++-language software development and code generation tool for microcontroller applications. DAVE is a standalone system with automatic code generation modules. It is suited for the development of software drivers for Infineon microcontrollers and aids the developer with automatically created C-level templates and user desired functionalities. Latest releases of DAVE include all required parts to develop code, compile and debug on the target for free (based on the ARM GCC toolsuite). Together with several low-cost development boards one can get involved in microcontroller design very easy. This makes Infineon microcontroller products also more usable to small companies and to home-use / DIY projects - similar to established products of Atmel (AVR, SAM) and Microchip (PIC, PIC32) to name a few. DAVE was developed by Infineon Technologies. Therefore, the automatic code generator supports only Infineon microcontrollers. The user also has to get used to the concept of the Eclipse IDE. The generated code can be also used on other (often non-free) development environments from Keil, Tasking and so on.
  • 916
  • 15 Nov 2022
Biography
William John Macquorn Rankine
William John Macquorn Rankine (/ˈræŋkɪn/) FRSE FRS LLD (5 July 1820 – 24 December 1872) was a Scottish mechanical engineer who also contributed to civil engineering, physics and mathematics. He was a founding contributor, with Rudolf Clausius and William Thomson (Lord Kelvin), to the science of thermodynamics, particularly focusing on the first of the three thermodynamic laws. He developed
  • 915
  • 30 Nov 2022
Biography
Alexander Bonner Latta
Alexander Bonner Latta (June 11, 1821 – April 28, 1865) was an American manufacturer and inventor. He produced the first practical steam fire engine that was successfully used as a routine part of a city's fire department equipment. Latta was born on a farm just outside the city limits of Chillicothe, Ohio, on July 11, 1821.[1] He was the youngest of six children and went by the nickname
  • 912
  • 08 Dec 2022
Topic Review
Surface Acoustic Wave
A surface acoustic wave (SAW) is an acoustic wave traveling along the surface of a material exhibiting elasticity, with an amplitude that typically decays exponentially with depth into the material. Materials with relatively high magnitude of Young's modulus (e.g., buildings) can be destructed once exposed to strong SAWs (as in earthquakes), whereas, those with relatively low Young's modulus (e.g., bubbles,and biological cells) can start to oscillate when driven by weak SAWs.
  • 911
  • 03 Nov 2022
Topic Review
GPS Block IIIA
GPS Block IIIA consists of the first ten (known as "tranche") of GPS III satellites, which will be used to keep the Navstar Global Positioning System operational. Lockheed Martin designed, developed and manufactured the GPS III Non-Flight Satellite Testbed (GNST) and all ten Block IIIA satellites. The first satellite in the series was projected to launch in 2014, but significant delays have pushed the scheduled launch to December 2018. The tenth and final GPS Block IIIA launch is projected in Q2 2023.
  • 911
  • 10 Nov 2022
Topic Review
Boiling Water Reactor
A boiling water reactor (BWR) is a type of light water nuclear reactor used for the generation of electrical power. It is the second most common type of electricity-generating nuclear reactor after the pressurized water reactor (PWR), which is also a type of light water nuclear reactor. The main difference between a BWR and PWR is that in a BWR, the reactor core heats water, which turns to steam and then drives a steam turbine. In a PWR, the reactor core heats water, which does not boil. This hot water then exchanges heat with a lower pressure system, which turns water into steam that drives the turbine. The BWR was developed by the Argonne National Laboratory and General Electric (GE) in the mid-1950s. The main present manufacturer is GE Hitachi Nuclear Energy, which specializes in the design and construction of this type of reactor.
  • 910
  • 24 Nov 2022
Topic Review
Bronze and Brass Ornamental Work
The use of bronze dates from remote antiquity. This important metal is an alloy composed of copper and tin, in proportion which vary slightly, but may be normally considered as nine parts of copper to one of tin. Other ingredients which are occasionally found are more or less accidental. The result is a metal of a rich golden brown colour, capable of being worked by casting — a process little applicable to its component parts, but peculiarly successful with bronze, the density and hardness of the metal allowing it to take any impression of a mould, however delicate. It is thus possible to create ornamental work of various kinds. The process of casting is known as cire perdue, and is the most primitive and most commonly employed through the centuries, having been described by the monk Theophilus, and also by Benvenuto Cellini. Briefly, it is as follows: a core, roughly representing the size and form of the object to be produced, is made of pounded brick, plaster or other similar substance and thoroughly dried. Upon this the artist overlays his wax, which he models to the degree required in his finished work. Passing from the core through the wax and projecting beyond are metal rods. The modelling being completed, called lost-wax casting, the outer covering which will form the mould has to be applied; this is a liquid formed of clay and plaster sufficiently thin to find its way into every detail of the wax model. Further coatings of liquid are applied, so that there is, when dry, a solid outer coating and a solid inner core held together by the metal rods, with the work of art modelled in wax between. Heat is applied and the wax melts and runs out, and the molten metal is poured in and occupies every detail which the wax had filled. When cool, the outer casing is carefully broken away, the core raked out as far as possible, the projecting rods are removed and the object modelled in wax appears in bronze. If further finish is required, it is obtained by tooling.
  • 906
  • 28 Nov 2022
Topic Review
TiO2 for Removal of VOCs
Purification of air from the VOCs (Volatile Organic Compounds) by the photocatalytic process has been confirmed to be very perspective. Although many various photocatalysts have been prepared and studied so far, TiO2 is still the most commonly used, because of its advantageous properties such as non-toxicity, relatively low cost and high stability. Surface modifications of TiO2 were extensively proceeded in order to increase photocatalytic activity of the photocatalyst under both UV and visible light activations. High yield of VOCs decomposition can be achieved on TiO2, depending on its structure and preparation method. The contact time of reactant with the active sites of TiO2 surface will determinate the efficiency of the photocatalytic process. Although VOCs decomposition can occur under weak UV light, more intensive UV irradiation will guarante complete mineralisation process. 
  • 903
  • 22 Apr 2021
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