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Topic Review
Optical Switch
An optical switch is a device that selectively switches optical signals from one channel to another. The switching can be temporal or spatial. The former is known as an optical (time-domain) switch or an optical modulator, while the latter is called an optical space switch or an optical router. In general, optical modulators and routers can be made from each other.
  • 2.3K
  • 17 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.
  • 2.3K
  • 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.
  • 2.3K
  • 27 Oct 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.
  • 2.3K
  • 09 Oct 2022
Topic Review
Flow Battery
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.
  • 2.3K
  • 12 Oct 2022
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. 
  • 2.3K
  • 30 Mar 2021
Topic Review
Comparison of Remote Sensing Satellites
A variety of remote sensing systems exist, for which the specification is distributed among a variety of websites from data providers, satellite operators and manufacturers. In order to choose a data product for a given project, a remote sensing data user must be aware of the different products and their applications. The table below gives users an overview of major remote sensing systems and datasets and summarizes their applications and systems.
  • 2.3K
  • 20 Oct 2022
Biography
Alan Bovik
Alan Conrad Bovik (born June 25, 1958) is an American engineer and vision scientist. He is a Professor at The University of Texas at Austin (UT-Austin), where he holds the Cockrell Family Regents Endowed Chair and is Director of the Laboratory for Image and Video Engineering (LIVE). He is a faculty member in the UT-Austin Department of Electrical and Computer Engineering (UT ECE), the Institute
  • 2.3K
  • 23 Nov 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.
  • 2.3K
  • 08 Nov 2022
Topic Review
Homemade Firearm
Homemade firearms are small improvised firearms built by individuals from kits or other equipment, which are generally excepted from commercial firearms markets or regulations. The phenomenon is most popular in the United States , where it is a political issue for gun control advocates, gun rights advocates, and law enforcement. Homemade guns are in general legal. Homemade guns are generally not subject to federal or state commercial background check regulations.
  • 2.3K
  • 18 Oct 2022
Topic Review
Plastic Surgery
Plastic surgery is a surgical specialty involving the restoration, reconstruction, or alteration of the human body. It can be divided into two main categories: reconstructive surgery and cosmetic surgery. Reconstructive surgery includes craniofacial surgery, hand surgery, microsurgery, and the treatment of burns. While reconstructive surgery aims to reconstruct a part of the body or improve its functioning, cosmetic (or aesthetic) surgery aims at improving the appearance of it. Both of these techniques are used throughout the world.
  • 2.2K
  • 20 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
Thermal Analysis in Biomass Combustion
Driven by its accessibility, extensive availability, and growing environmental consciousness, solid biomass has emerged as a viable alternative to enhance the diversity of renewable energy sources for electricity generation. To understand the phenomena involved in solid biomass conversion, it is necessary not only to understand the stages of the biomass combustion process but also to understand specifically the kinetics of the reaction and the release of the volatiles.
  • 2.2K
  • 07 Oct 2023
Biography
John Hick
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
Mineral Processing
In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores.
  • 2.2K
  • 27 Oct 2022
Topic Review
Sound Trap
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.
  • 2.2K
  • 25 Oct 2022
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
  • 2.2K
  • 26 Dec 2022
Biography
Percy Spencer
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
  • 2.2K
  • 27 Dec 2022
Topic Review
Indonesian Car
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.
  • 2.2K
  • 16 Nov 2022
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