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Topic Review

Desalination in China

In recent decades, the ever-growing demands for clean water in households and industries have urged researchers to take every possible step to deal with the global water crisis. Seawater desalination has turned out to be the most promising and efficient way to provide clean water. Owing to the advancement of synthetic chemistries and technologies, great success has been achieved in the desalination and utilization of seawater worldwide. China, with the world’s largest population, has pushed the development of desalination and multipurpose utilization of seawater further in respect of materials, technologies and services, etc.

2.2K
30 Mar 2021

Topic Review

Live, Virtual, and Constructive

Live, Virtual, & Constructive (LVC) Simulation is a broadly used taxonomy for classifying Models and Simulation (M&S). However, categorizing a simulation as a live, virtual, or constructive environment is problematic since there is no clear division between these categories. The degree of human participation in a simulation is infinitely variable, as is the degree of equipment realism. The categorization of simulations also lacks a category for simulated people working real equipment.

2.2K
02 Dec 2022

Topic Review

Computer-Supported Collaborative Learning

Computer-supported collaborative learning (CSCL) is a pedagogical approach wherein learning takes place via social interaction using a computer or through the Internet. This kind of learning is characterized by the sharing and construction of knowledge among participants using technology as their primary means of communication or as a common resource. CSCL can be implemented in online and classroom learning environments and can take place synchronously or asynchronously. The study of computer-supported collaborative learning draws on a number of academic disciplines, including instructional technology, educational psychology, sociology, cognitive psychology, and social psychology. It is related to collaborative learning and computer supported cooperative work (CSCW).

2.2K
01 Dec 2022

Topic Review

A flow battery, or redox flow battery (after reduction–oxidation), is a type of electrochemical cell where chemical energy is provided by two chemical components dissolved in liquids that are pumped through the system on separate sides of a membrane. Ion exchange (accompanied by flow of electric current) occurs through the membrane while both liquids circulate in their own respective space. Cell voltage is chemically determined by the Nernst equation and ranges, in practical applications, from 1.0 to 2.43 volts. A flow battery may be used like a fuel cell (where the spent fuel is extracted and new fuel is added to the system) or like a rechargeable battery (where an electric power source drives regeneration of the fuel). While it has technical advantages over conventional rechargeables, such as potentially separable liquid tanks and near unlimited longevity, current implementations are comparatively less powerful and require more sophisticated electronics. The energy capacity is a function of the electrolyte volume and the power is a function of the surface area of the electrodes.

2.2K
12 Oct 2022

Topic Review

European Hand Fans in the 18th Century

Hand fans first arrived in Europe in the 15th century from Asia and became popular in the 16th century. Several fan styles were common and a plethora of materials were used to create them. Subject matter varied greatly, from Biblical scenes to landscapes. Hand fans serve as a cooling mechanism, social instrument, and fashion accessory.

2.2K
30 Sep 2022

Topic Review

Conventional PCI

Conventional PCI, often shortened to PCI, is a local computer bus for attaching hardware devices in a computer. PCI is an abbreviation for Peripheral Component Interconnect and is part of the PCI Local Bus standard. The PCI bus supports the functions found on a processor bus but in a standardized format that is independent of any particular processor's native bus. Devices connected to the PCI bus appear to a bus master to be connected directly to its own bus and are assigned addresses in the processor's address space. It is a parallel bus, synchronous to a single bus clock. Attached devices can take either the form of an integrated circuit fitted onto the motherboard itself (called a planar device in the PCI specification) or an expansion card that fits into a slot. The PCI Local Bus was first implemented in IBM PC compatibles, where it displaced the combination of several slow ISA slots and one fast VESA Local Bus slot as the bus configuration. It has subsequently been adopted for other computer types. Typical PCI cards used in PCs include: network cards, sound cards, modems, extra ports such as USB or serial, TV tuner cards and disk controllers. PCI video cards replaced ISA and VESA cards until growing bandwidth requirements outgrew the capabilities of PCI. The preferred interface for video cards then became AGP, itself a superset of PCI, before giving way to PCI Express. The first version of PCI found in retail desktop computers was a 32-bit bus using a 33 MHz bus clock and 5 V signalling, although the PCI 1.0 standard provided for a 64-bit variant as well. These have one locating notch in the card. Version 2.0 of the PCI standard introduced 3.3 V slots, physically distinguished by a flipped physical connector to prevent accidental insertion of 5 V cards. Universal cards, which can operate on either voltage, have two notches. Version 2.1 of the PCI standard introduced optional 66 MHz operation. A server-oriented variant of PCI, called PCI-X (PCI Extended) operated at frequencies up to 133 MHz for PCI-X 1.0 and up to 533 MHz for PCI-X 2.0. An internal connector for laptop cards, called Mini PCI, was introduced in version 2.2 of the PCI specification. The PCI bus was also adopted for an external laptop connector standard – the CardBus. The first PCI specification was developed by Intel, but subsequent development of the standard became the responsibility of the PCI Special Interest Group (PCI-SIG). Conventional PCI and PCI-X are sometimes called Parallel PCI in order to distinguish them technologically from their more recent successor PCI Express, which adopted a serial, lane-based architecture. PCI's heyday in the desktop computer market was approximately 1995–2005. PCI and PCI-X have become obsolete for most purposes; however, they are still common on modern desktops for the purposes of backwards compatibility and the low relative cost to produce. Many kinds of devices previously available on PCI expansion cards are now commonly integrated onto motherboards or available in USB and PCI Express versions.

2.2K
27 Oct 2022

Topic Review

Light-Field Camera

A light field camera, also known as plenoptic camera, captures information about the light field emanating from a scene; that is, the intensity of light in a scene, and also the direction that the light rays are traveling in space. This contrasts with a conventional camera, which records only light intensity. One type of light field camera uses an array of micro-lenses placed in front of an otherwise conventional image sensor to sense intensity, color, and directional information. Multi-camera arrays are another type of light field camera. Holograms are a type of film-based light field image.

2.2K
26 Oct 2022

Topic Review

Server Immersion Cooling

Immersion cooling is an IT cooling practice by which IT components and other electronics, including complete servers, are submerged in a thermally conductive dielectric liquid or coolant. Heat is removed from the system by circulating liquid into direct contact with hot components, then through cool heat exchangers. Fluids suitable for immersion cooling have very good insulating properties to ensure that they can safely come into contact with energized electronic components.

2.2K
08 Nov 2022

Topic Review

Annealing (Metallurgy)

In metallurgy and materials science, annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness, making it more workable. It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooling. In annealing, atoms migrate in the crystal lattice and the number of dislocations decreases, leading to a change in ductility and hardness. As the material cools it recrystallizes. For many alloys, including carbon steel, the crystal grain size and phase composition, which ultimately determine the material properties, are dependent on the heating rate and cooling rate. Hot working or cold working after the annealing process alters the metal structure, so further heat treatments may be used to achieve the properties required. With knowledge of the composition and phase diagram, heat treatment can be used to adjust from harder and more brittle to softer and more ductile. In the case of ferrous metals, such as steel, annealing is performed by heating the material (generally until glowing) for a while and then slowly letting it cool to room temperature in still air. Copper, silver and brass can be either cooled slowly in air, or quickly by quenching in water. In this fashion, the metal is softened and prepared for further work such as shaping, stamping, or forming.

2.2K
09 Oct 2022

Biography

John Hick JP DL MP FRSA (2 July 1815 – 2 February 1894) was a wealthy[1] English industrialist, art collector and Conservative Party politician who sat in the House of Commons from 1868 to 1880.[2][3] He is associated with the improvement of steam-engines for cotton mills and the work of his firm Hick, Hargreaves and Co. universal in countries where fibre was spun or fabrics woven.[4] Hick

2.2K
01 Dec 2022

Topic Review

List of Devices with Gorilla Glass

With the expanded use of touchscreen mobile phones, mobile makers started looking for scratch-resistant solutions for the bigger mobile displays. Here is a list of mobile phones and tablets that make use of the Gorilla Glass technology developed by Corning Incorporated from various makes: Though this list is sourced from Corning's website, there is a statement on that site indicating that this list is not necessarily comprehensive, as some companies have contractual arrangements with Corning that prohibit listing of said companies' products.

2.2K
26 Oct 2022

Topic Review

Loss-of-Coolant Accident

A loss-of-coolant accident (LOCA) is a mode of failure for a nuclear reactor; if not managed effectively, the results of a LOCA could result in reactor core damage. Each nuclear plant's emergency core cooling system (ECCS) exists specifically to deal with a LOCA. Nuclear reactors generate heat internally; to remove this heat and convert it into useful electrical power, a coolant system is used. If this coolant flow is reduced, or lost altogether, the nuclear reactor's emergency shutdown system is designed to stop the fission chain reaction. However, due to radioactive decay, the nuclear fuel will continue to generate a significant amount of heat. The decay heat produced by a reactor shutdown from full power is initially equivalent to about 5 to 6% of the thermal rating of the reactor. If all of the independent cooling trains of the ECCS fail to operate as designed, this heat can increase the fuel temperature to the point of damaging the reactor. Under operating conditions, a reactor may passively (that is, in the absence of any control systems) increase or decrease its power output in the event of a LOCA or of voids appearing in its coolant system (by water boiling, for example). This is measured by the coolant void coefficient. Most modern nuclear power plants have a negative void coefficient, indicating that as water turns to steam, power instantly decreases. Two exceptions are the Soviet RBMK and the Canadian CANDU. Boiling water reactors, on the other hand, are designed to have steam voids inside the reactor vessel. Modern reactors are designed to prevent and withstand loss of coolant, regardless of their void coefficient, using various techniques. Some, such as the pebble bed reactor, passively slow down the chain reaction when coolant is lost; others have extensive safety systems to rapidly shut down the chain reaction, and may have extensive passive safety systems (such as a large thermal heat sink around the reactor core, passively-activated backup cooling/condensing systems, or a passively cooled containment structure) that mitigate the risk of further damage.

2.1K
09 Oct 2022

Topic Review

Taurus Millennium Series

The Taurus Millennium series is a product line of double-action only (DAO) and single-action/double-action hammerless, striker-fired, short recoil operated, semi-automatic pistols manufactured by Forjas Taurus S/A (Taurus Forge) in Porto Alegre Brazil . The Millennium line was designed to contend in the civilian concealed carry firearms market, and to be sold as backup weapons for law enforcement officers.

2.1K
30 Nov 2022

Topic Review

Indonesian national car is the categorization of a Low Cost Green Car (LCGC) in Indonesia with the following initial specifications: Priced between 50,000,000 Indonesian rupiah for villagers to Rp 85,000,000 for the general public[1]; Fuel efficiency of at least 20 km/l (56 mpg‑imp; 47 mpg‑US); Made up from at least 60% domestic components.

2.1K
16 Nov 2022

Biography

Percy Lebaron Spencer (July 19, 1894 – September 8, 1970) was an United States physicist and inventor. He became known as the inventor of the microwave oven.[1] Spencer was born in Howland, Maine. Eighteen months later, Spencer's father died, and his mother soon left him in the care of his aunt and uncle. His uncle then died when Spencer was just seven years old. Spencer subsequently left g

2.1K
27 Dec 2022

Biography

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

2.1K
26 Dec 2022

Topic Review

A sound trap, also known as a duct silencer, sound attenuator, or muffler, is a special 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 trap consists of an baffle within the ductwork. These baffles often contain sound-absorbing materials. The physical dimensions and baffle configuration of sound traps 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 traps can achieve broader band attenuation in relatively short lengths. Certain types of sound traps are essentially a Helmholtz resonator used as a passive noise-control device.

2.1K
25 Oct 2022

Topic Review

Microchip Implant (Animal)

A microchip implant is an identifying integrated circuit placed under the skin of an animal. The chip, about the size of a large grain of rice, uses passive radio-frequency identification (RFID) technology, and is also known as a PIT (passive integrated transponder) tag. Standard pet microchips are typically 11–13 mm long (approximately 1⁄2 inch) and 2 mm in diameter. Externally attached microchips such as RFID ear tags are commonly used to identify farm and ranch animals, with the exception of horses. Some external microchips can be read with the same scanner used with implanted chips. Animal shelters, animal control officers and veterinarians routinely look for microchips to return lost pets quickly to their owners, avoiding expenses for housing, food, medical care, outplacing and euthanasia. Many shelters place chips in all outplaced animals. Microchips are also used by kennels, breeders, brokers, trainers, registries, rescue groups, humane societies, clinics, farms, stables, animal clubs and associations, researchers, and pet stores.

2.1K
12 Oct 2022

Biography

Robert “Bob” Zeidman (born January 18, 1960) is an American electrical engineer, educator and inventor who has made contributions in Application Specific Integrated Circuit (ASIC) design, Field Programmable Gate Array (FPGA) design, embedded systems development, software synthesis, software analysis and software forensics. Best known as the inventor of software forensics,[1][2] Zeidman’s p

2.1K
25 Nov 2022

Topic Review

Homi (Korean: 호미), also known as a Korean hand plow, is a short-handled traditional farming tool used by Koreans. It is a farming tool that removes grasses from paddies and fields. It is also used when plowing a rice field, planting seeds, plowing up soil, and digging potatoes in fields. It is a farming tool similar to the hoe. It is an important extension of agriculture from the ancient times because the homi was excavated in the Bronze Age historic site of the Pyeongnam Mangsan Daepyeong-ri and the early Iron Age historic site of Yangpyong, Gyeonggi Province. Homi is distributed nationwide, but they are characterized by locality. In other words, homi is classified into Plowshare-shaped(보습형), Sickle-shaped(낫형), and Triangle-shaped(세모형) depending on the natural conditions of the local area and the characteristics of agricultural management.

2.1K
26 Oct 2022

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