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Topic Review
Pocket-Sized Computer
Pocket-sized computer describes the post-programmable calculator / pre-smartphone pocket-sized portable-office hardware devices that included the earlier DOS-based palmtops and subsequent Windows-CE handhelds, as well as a few other terms, primarily covering the 1980s through 2007. Sometimes called Pocket-sized computing devices, they were a series of internally different devices, and included Handheld ("Pocket-sized handheld computing device"), and the earlier-introduced Palmtop ("Pocket-sized palmtop computing device") and "pocket-sized palmtop computer." The New York Times used the term "palmtop/handheld." The media called "the first computer that fits in your palm and weighs less than a pound" and its early day competitors a palmtop. Although the word "handheld" was used before Microsoft's 1996 introduction of Windows CE, a lawsuit by Palm, Inc pushed Microsoft's use of the new term Handheld PC. By 2007, the iPhone began to replace prior portable office devices, and by a decade later there were indications that "SmartGlasses" might be their replacement.
  • 3.4K
  • 28 Nov 2022
Topic Review
Freight Bicycle
Freight bicycles, carrier cycles, freight tricycles, cargo bikes, box bikes, or cycletrucks are human powered vehicles designed and constructed specifically for transporting loads. Vehicle designs include a cargo area consisting of an open or enclosed box, a flat platform, or a wire basket, usually mounted over one or both wheels, low behind the front wheel, or between parallel wheels at either the front or rear of the vehicle. The frame and drivetrain must be constructed to handle loads larger than those on an ordinary bicycle.
  • 3.4K
  • 03 Jan 2023
Topic Review
Freeze-Drying of Foods
Freeze-drying is a process in which water is sublimated by the direct transition of water from solid (ice) to vapor, thus omitting the liquid state, and then desorbing water from the “dry” layer.
  • 3.4K
  • 16 Nov 2020
Topic Review
Mac Transition to Apple Silicon
The Mac transition to Apple Silicon is the planned two-year process of introducing ARM64-based Apple silicon to, and deprecating Intel's x86-64 from, Apple's Macintosh line of computers. CEO Tim Cook announced the plan in his WWDC keynote address on June 22, 2020. The transition is the third time Apple has migrated Macintosh to a new instruction set architecture (ISA). The first was the switch from the Mac's original Motorola 68000 series architecture to the new PowerPC platform in 1994, and the second was the transition from PowerPC to Intel x86, which was formally announced in June 2005. Apple first utilized the ARM architecture in 1993 in its Newton personal digital assistant, and since then has extensively deployed it throughout other product lines including iPhone, iPad, iPod, and Apple Watch. Apple has designed its own custom ARM chips since 2009.
  • 3.4K
  • 02 Nov 2022
Biography
Robert Fulton
Robert Fulton (November 14, 1765 – February 25, 1815) was an United States engineer and inventor who is widely credited with developing a commercially successful steamboat; the first was called The North River Steamboat of Clermonts. In 1807 that steamboat traveled on the Hudson River with passengers from New York City to Albany and back again, a round trip of 300 miles, in 62 hours. The succe
  • 3.3K
  • 25 Nov 2022
Topic Review
Ordnance QF 75 Mm
The Ordnance QF 75 mm, abbreviated to OQF 75 mm, was a British tank-gun of the Second World War. It was obtained by boring out the Ordnance QF 6 pounder ("6 pdr") 57-mm anti-tank gun to 75-mm, to give better performance against infantry targets in a similar fashion to the 75mm M3 gun fitted to the American Sherman tank. The QF came from "quick-firing", referring to the use of ammunition with the shell and propellant in a single cartridge. The gun was also sometimes known as ROQF from Royal Ordnance (the manufacturer) Quick-Firing.
  • 3.3K
  • 02 Nov 2022
Topic Review
Zellige
Zellige (Arabic: [zˈliʑ]; Arabic: الزليج; also zelige or zellij) is mosaic tilework made from individually chiseled geometric tiles set into a plaster base. This form of Islamic art is one of the main characteristics of Moroccan architecture. It consists of geometrically patterned mosaics, used to ornament walls, ceilings, fountains, floors, pools and tables.
  • 3.3K
  • 06 Oct 2022
Topic Review
Luxury Yacht
A Luxury yacht (also super-yacht, large yacht and mega-yacht) is a very expensive, privately owned, professionally crewed sailing or motor yacht. There is no industry-wide standard for the difference between super-yacht and mega-yacht. The only legal distinction is between yachts above 24 metres (79 ft) and below, as in some countries those above 24 meters must have a permanent crew onboard. This term began to appear at the beginning of the 20th century, when wealthy individuals constructed large private yachts for personal pleasure, such as Charles Henry Fletcher's Jemima F. III, at 111 feet, the largest motor-powered yacht in the world in 1908. More examples of early luxury motor yachts include the Cox & King yachts, Charles L. Seabury and Company's yachts, M/Y (motor yacht) Christina O, and M/Y Savarona.
  • 3.3K
  • 21 Nov 2022
Topic Review
Modified Frequency Modulation
Modified Frequency Modulation, commonly MFM, is a run-length limited (RLL) coding scheme used to encode the actual data-bits on most floppy disks. It was first introduced in disk drives with the IBM 3330 hard disk drive in 1970. Floppy disk drive hardware examples include Amiga, most CP/M machines as well as IBM PC compatibles. MFM is a modification to the original digital FM (digital frequency modulation also known as delay coding) scheme for encoding data on single-density floppy disks and some early hard disk drives. Due to the minimum spacing between flux transitions that is a property of the disk, head and channel design, MFM, which guarantees at most one flux transition per data bit, can be written at higher density than FM, which can require two transitions per data bit. It is used with a data rate of 250–500 kbit/s (500–1000 kbit/s encoded) on industry standard 5¼-inch and 3½-inch ordinary and high density diskettes. MFM was also used in early hard disk designs, before the advent of more efficient types of run-length limited codes. Except for the steadily disappearing 360 KiB/1.2 MiB (5.25-inch) and 720~880 KiB/1.4~1.6 MiB (3.5-inch) floppy disk formats, MFM encoding is obsolete in magnetic recording.
  • 3.3K
  • 22 Nov 2022
Topic Review
Struvite Precipitation Technologies
The abatement of nutrient compounds from aqueous waste and wastewater is currently a priority issue. Indeed, the uncontrolled discharge of high levels of nutrients into water bodies causes serious deteriorations of environmental quality. On the other hand, the increasing request of nutrient compounds for agronomic utilizations makes it strictly necessary to identify technologies able to recover the nutrients from wastewater streams so as to avoid the consumption of natural resources. In this regard, the removal and recovery of nitrogen and phosphorus from aqueous waste and wastewater as struvite (MgNH4PO4·6H2O) represents an attractive approach. Indeed, through the struvite precipitation it is possible to effectively remove the ammonium and phosphate content of many types of wastewater and to produce a solid compound, with only a trace of impurities. This precipitate, due to its chemical characteristics, represents a valuable multi-nutrients slow release fertilizer for vegetables and plants growth. For these reasons, the struvite precipitation technology constantly progresses on several aspects of the process.
  • 3.3K
  • 08 Feb 2021
Topic Review
Wind Hybrid Power Systems
Wind hybrid power systems combines wind turbines with other storage and/or generation sources. One of the key issues with wind energy is its intermittent nature. This has led to numerous methods of storing energy.
  • 3.3K
  • 11 Oct 2022
Topic Review
Medical Thermometer
A medical thermometer (also called clinical thermometer) is used for measuring human or animal body temperature. The tip of the thermometer is inserted into the mouth under the tongue (oral or sub-lingual temperature), under the armpit (axillary temperature), into the rectum via the anus (rectal temperature), into the ear (tympanic temperature), or on the forehead (temporal temperature).
  • 3.2K
  • 04 Nov 2022
Topic Review
EM-2 Rifle
The EM-2, also known as Rifle No.9 Mk1 or Janson rifle, was an experimental United Kingdom assault rifle. It was briefly adopted by British forces in 1951, but the decision was overturned very shortly thereafter by Winston Churchill's incoming government in an effort to secure NATO standardisation of small arms and ammunition. An innovative weapon with the compact bullpup layout and an optical sight, it used one of the early intermediate cartridges (a concept introduced by the Germans with the 7.92×33mm Kurz) as a result of combat experience and German advances in weapons design during World War II. It used the experimental, intermediate powered, but highly efficient .280 British round, which was designed to replace the venerable .303 round and Lee–Enfield rifle variants which had served since before the turn of the 20th century. The United States claimed the .280 British round was too weak for use in rifles and machine guns, and instead favored the much more powerful 7.62×51mm NATO round. As the EM-2 could not be easily adapted to the longer and more powerful round, it faded from use. However, the bullpup layout for a British service rifle was finally adopted some years later in form of the SA80 assault rifle, the EM-2's spiritual successor, which remains in service today.
  • 3.2K
  • 18 Nov 2022
Topic Review
Classic Car
A classic car is an older automobile; the exact definition varies around the world. The common theme is of an older car with enough historical interest to be collectable and worth preserving or restoring rather than scrapping. Cars 20 years and older typically fall into the classic class. Organizations such as the Classic Car Club of America (CCCA) and the Antique Automobile Club of America (AACA) maintain a list of eligible unmodified cars that are called "classic". These are described as "fine" or "distinctive" automobile, either American or foreign built, produced between 1915 to 1998. Post–World War II "classic cars" are not precisely defined and the term is often applied to any older vehicle.
  • 3.2K
  • 02 Nov 2022
Topic Review
Virtual Reality and Robots
There is a significant amount of synergy between virtual reality (VR) and the field of robotics. However, it has only been in approximately the past five years that commercial immersive VR devices have been available to developers. This new availability has led to a rapid increase in research using VR devices in the field of robotics, especially in the development of VR interfaces for operating robots. 
  • 3.2K
  • 25 Jan 2021
Topic Review
Sound Attenuators
A sound attenuator, or duct silencer, sound trap, or muffler, is a noise control acoustical treatment of Heating Ventilating and Air-Conditioning (HVAC) ductwork designed to reduce transmission of noise through the ductwork, either from equipment into occupied spaces in a building, or between occupied spaces. In its simplest form, a sound attenuator consists of an baffle within the ductwork. These baffles often contain sound-absorbing materials. The physical dimensions and baffle configuration of sound attenuators are selected to attenuate a specific range of frequencies. Unlike conventional internally-lined ductwork, which is only effective at attenuating mid- and high-frequency noise, sound attenuators can achieve broader band attenuation in relatively short lengths. Certain types of sound attenuators are essentially a Helmholtz resonator used as a passive noise-control device.
  • 3.2K
  • 27 Oct 2022
Topic Review
Electricity Tariffs and Solutions for Optimal Energy Management
Today, electricity tariffs play an essential role in the electricity retail market as they are the key factor for the decision-making of end-users. Additionally, tariffs are necessary for increasing competition in the electricity market. They have a great impact on load energy management. Moreover, tariffs are not taken as a fixed approach to expense calculations only but are influenced by many other factors, such as electricity generation, transmission, distribution costs, and governmental taxation. Thus, electricity pricing differs significantly between countries or between regions within a country. Improper tariff calculation methodologies in some areas have led to high-power losses, unnecessary investments, increased operational expenses, and environmental pollution due to the non-use of available sustainable energy resources.
  • 3.2K
  • 25 Nov 2022
Topic Review
Kīla (Buddhism)
The kīla or phurba (Sanskrit Devanagari: कील; IAST: kīla; Tibetan: ཕུར་པ or ཕུར་བ, Wylie: phur ba, alternate transliterations and English orthographies: phurpa, phurbu, purbha, or phurpu) is a three-sided peg, stake, knife, or nail-like ritual implement traditionally associated with Indo-Tibetan Buddhism, Bön, and Indian Vedic traditions. The kīla is associated with the practice of the yidam (Sanskrit ishtadevata, Tibetan yidam) or meditational deity Vajrakīla (वज्रकील) or Vajrakīlaya (Tibetan Dorje Phurba).
  • 3.2K
  • 23 Nov 2022
Topic Review
Microplastics
Plastics are broken down to microplastics (MPs), which are <5 mm in size. There are two types of MPs—primary MPs that are intentionally manufactured (detergent) and secondary MPs that are generated via mechanical collision, biodegradation, and photo-oxidative degradation of primary MPs. Both types of MPs carry toxic organic pollutants and heavy metals, since they have large surface areas and strong hydrophobicity. Microplastic (MP)-based contaminants in the environment are pervasive, but standard technologies used for MP identification have not yet been reported. Human beings take up MPs from the environmental ecosystem through the food chain without any particular purification. MPs can penetrate into capillaries from the bloodstream, resulting in endocrine system disorders or toxicity.In this review, we introduced several technologies, such as filtration using membranes, biological degradation, electrocoagulation, and removal using nanoparticles, used for the purification of MPs or related contaminants. Current studies of identification methods of MPs and evaluation tests of MPs exposure-based harmfulness in vitro and in vivo were summarized.
  • 3.2K
  • 21 Dec 2020
Topic Review
Roman Engineering
The ancient Romans were famous for their advanced engineering accomplishments, although some of their inventions were improvements on older ideas, concepts and inventions. Technology for bringing running water into cities was developed in the east, but transformed by the Romans into a technology inconceivable in Greece. The architecture used in Rome was strongly influenced by Greek and Etruscan sources. Roads were common at that time, but the Romans improved their design and perfected the construction to the extent that many of their roads are still in use today. Their accomplishments surpassed most other civilizations of their time, and after their time, and many of their structures have withstood the test of time to inspire others, especially during the Renaissance. Moreover, their contributions were described in some detail by authors such as Vitruvius, Frontinus and Pliny the Elder, so there is a printed record of their many inventions and achievements.
  • 3.2K
  • 27 Oct 2022
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