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Islamic Republic of Afghanistan
In 2009, the Super Tucano was offered in a U.S. Air Force competition for 100 counterinsurgency aircraft. On 12 April 2010, Brazil signed an agreement to open negotiations for the acquisition of 200 Super Tucanos by the U.S. On 16 November 2011, the AT-6 was excluded from the LAS progra... | Embraer EMB 314 Super Tucano | Wikipedia | 504 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Bolivia
Embraer reportedly offered the Super Tucano to the Bolivian Air Force.
Equatorial Guinea
Equatorial Guinea was said to be interested in purchasing the Super Tucano.
Guatemala
In August 2011, the Guatemalan Air Force requested credit approval of $166 million to buy six EMB-314s, control centers, radar, and ... | Embraer EMB 314 Super Tucano | Wikipedia | 440 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
UAE
In September 2010, it was announced that Brazil and the United Arab Emirates were working a deal that includes sales of Super Tucanos. It was reported in early 2015 that the UAE is negotiating with Embraer the purchase of 24 Super Tucanos, the deal would include six aircraft from Brazilian Air Force inventory for ... | Embraer EMB 314 Super Tucano | Wikipedia | 457 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Senegal
In September 2012, Senegal was reportedly in a procurement process with Embraer. In April 2013, the Brazilian minister of Defence disclosed that Senegal was the 4th African nation to order the Super Tucano, in the following day, Embraer confirmed the order, which included a training system for pilots and mechan... | Embraer EMB 314 Super Tucano | Wikipedia | 425 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Brazilian Air Force – 99 aircraft (33 A-29A & 66 A-29B). At least four aircraft have been lost.
1st Squadron of the 3rd Aviation Group (1º/3º GAv) "Esquadrão Escorpião" (Scorpion Squadron)
2nd Squadron of the 3rd Aviation Group (2º/3º GAv) "Esquadrão Grifo" (Griffon Squadron)
3rd Squadron of the 3rd Aviation Group (... | Embraer EMB 314 Super Tucano | Wikipedia | 445 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Ghana Air Force – 5 aircraft ordered in 2015. The total value of the contract was $88million with a loan from BNDES, which also includes logistics support and training for pilots and mechanics in Ghana. The first aircraft were expected to arrive in late 2016, and will be used as advanced training, border surveillance a... | Embraer EMB 314 Super Tucano | Wikipedia | 476 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Nigerian Air Force – 12 aircraft on order. First batch with 6 aircraft delivered on 22 July 2021, and the delivery was completed with the arrival of the final batch to Nigeria in October 2021.
Paraguayan Air Force – 6 aircraft ordered in July 2024, with deliveries planned to begin in 2025.
Philippine Air Force ... | Embraer EMB 314 Super Tucano | Wikipedia | 361 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
Accidents
On 10 February 2016, an Indonesian Air Force Embraer EMB-314 Super Tucano crashed in Malang, East Java, on suburb area near Abdul Rachman Saleh Air Base. The aircraft (TT-3108) was on a routine test flight. Both pilots and two civilians died in the accident.
On 15 August 2021, an Embraer 314 aircraft belongin... | Embraer EMB 314 Super Tucano | Wikipedia | 307 | 5133204 | https://en.wikipedia.org/wiki/Embraer%20EMB%20314%20Super%20Tucano | Technology | Specific aircraft | null |
In astronomy, the geometric albedo of a celestial body is the ratio of its actual brightness as seen from the light source (i.e. at zero phase angle) to that of an idealized flat, fully reflecting, diffusively scattering (Lambertian) disk with the same cross-section. (This phase angle refers to the direction of the lig... | Geometric albedo | Wikipedia | 439 | 5139283 | https://en.wikipedia.org/wiki/Geometric%20albedo | Physical sciences | Planetary science | Astronomy |
For very bright, solid, airless objects such as Saturn's moons Enceladus and Tethys, whose total reflectance (Bond albedo) is close to one, a strong opposition effect combines with the high Bond albedo to give them a geometric albedo above unity (1.4 in the case of Enceladus). Light is preferentially reflected straight... | Geometric albedo | Wikipedia | 370 | 5139283 | https://en.wikipedia.org/wiki/Geometric%20albedo | Physical sciences | Planetary science | Astronomy |
In complexity theory, a time-constructible function is a function f from natural numbers to natural numbers with the property that f(n) can be constructed from n by a Turing machine in the time of order f(n). The purpose of such a definition is to exclude functions that do not provide an upper bound on the runtime of s... | Constructible function | Wikipedia | 449 | 906783 | https://en.wikipedia.org/wiki/Constructible%20function | Mathematics | Complexity theory | null |
Examples
All the commonly used functions f(n) (such as n, nk, 2n) are time- and space-constructible, as long as f(n) is at least cn for a constant c > 0. No function which is o(n) can be time-constructible unless it is eventually constant, since there is insufficient time to read the entire input. However, is a space-... | Constructible function | Wikipedia | 242 | 906783 | https://en.wikipedia.org/wiki/Constructible%20function | Mathematics | Complexity theory | null |
A metamaterial (from the Greek word μετά meta, meaning "beyond" or "after", and the Latin word materia, meaning "matter" or "material") is a type of material engineered to have a property, typically rarely observed in naturally occurring materials, that is derived not from the properties of the base materials but from ... | Metamaterial | Wikipedia | 460 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Explorations of artificial materials for manipulating electromagnetic waves began at the end of the 19th century. Some of the earliest structures that may be considered metamaterials were studied by Jagadish Chandra Bose, who in 1898 researched substances with chiral properties. Karl Ferdinand Lindman studied wave inte... | Metamaterial | Wikipedia | 474 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
In 2000, David R. Smith et al. reported the experimental demonstration of functioning electromagnetic metamaterials by horizontally stacking, periodically, split-ring resonators and thin wire structures. A method was provided in 2002 to realize negative-index metamaterials using artificial lumped-element loaded transmi... | Metamaterial | Wikipedia | 416 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
The unusual properties of metamaterials arise from the resonant response of each constituent element rather than their spatial arrangement into a lattice. It allows considering the local effective material parameters (permittivity and permeability). The resonance effect related to the mutual arrangement of elements is ... | Metamaterial | Wikipedia | 502 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Electromagnetic metamaterials can be divided into different classes, as follows:
Negative refractive index
Negative-index metamaterials (NIM) are characterized by a negative index of refraction. Other terms for NIMs include "left-handed media", "media with a negative refractive index", and "backward-wave media". NIMs... | Metamaterial | Wikipedia | 496 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
For plane waves propagating in electromagnetic metamaterials, the electric field, magnetic field and wave vector follow a left-hand rule, the reverse of the behavior of conventional optical materials.
To date, only metamaterials exhibit a negative index of refraction.
Single negative
Single negative (SNG) metamateria... | Metamaterial | Wikipedia | 425 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Hyperbolic
Hyperbolic metamaterials (HMMs) behave as a metal for certain polarization or direction of light propagation and behave as a dielectric for the other due to the negative and positive permittivity tensor components, giving extreme anisotropy. The material's dispersion relation in wavevector space forms a hyp... | Metamaterial | Wikipedia | 486 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
EBGs have been manufactured for frequencies ranging from a few gigahertz (GHz) to a few terahertz (THz), radio, microwave and mid-infrared frequency regions. EBG application developments include a transmission line, woodpiles made of square dielectric bars and several different types of low gain antennas.
Double posit... | Metamaterial | Wikipedia | 509 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
where and are the permittivity and the permeability tensors, respectively, whereas and are the two magneto-electric tensors. If the medium is reciprocal, permittivity and permeability are symmetric tensors, and , where is the chiral tensor describing chiral electromagnetic and reciprocal magneto-electric resp... | Metamaterial | Wikipedia | 254 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Generally a chiral and/or bianisotropic electromagnetic response is a consequence of 3D geometrical chirality: 3D-chiral metamaterials are composed by embedding 3D-chiral structures in a host medium and they show chirality-related polarization effects such as optical activity and circular dichroism. The concept of 2D c... | Metamaterial | Wikipedia | 467 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Frequency selective surface-based metamaterials block signals in one waveband and pass those at another waveband. They have become an alternative to fixed frequency metamaterials. They allow for optional changes of frequencies in a single medium, rather than the restrictive limitations of a fixed frequency response.
O... | Metamaterial | Wikipedia | 478 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Metamaterials may be fabricated that include some form of nonlinear media, whose properties change with the power of the incident wave. Nonlinear media are essential for nonlinear optics. Most optical materials have a relatively weak response, meaning that their properties change by only a small amount for large change... | Metamaterial | Wikipedia | 481 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Meta-biomaterials
Meta-biomaterials have been purposefully crafted to engage with biological systems, amalgamating principles from both metamaterial science and biological areas. Engineered at the nanoscale, these materials adeptly manipulate electromagnetic, acoustic, or thermal properties to facilitate biological pr... | Metamaterial | Wikipedia | 503 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
A metamaterial absorber manipulates the loss components of metamaterials' permittivity and magnetic permeability, to absorb large amounts of electromagnetic radiation. This is a useful feature for photodetection and solar photovoltaic applications. Loss components are also relevant in applications of negative refractiv... | Metamaterial | Wikipedia | 501 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Guided mode manipulations
Metamaterials can be integrated with optical waveguides to tailor guided electromagnetic waves (meta-waveguide). Subwavelength structures like metamaterials can be integrated with for instance silicon waveguides to develop and polarization beam splitters and optical couplers, adding new degre... | Metamaterial | Wikipedia | 397 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
Three-dimensional composites of metal/non-metallic inclusions periodically/randomly embedded in a low permittivity matrix are usually modeled by analytical methods, including mixing formulas and scattering-matrix based methods. The particle is modeled by either an electric dipole parallel to the electric field or a pai... | Metamaterial | Wikipedia | 400 | 906878 | https://en.wikipedia.org/wiki/Metamaterial | Physical sciences | Basics_9 | null |
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". Organisms living in this zone are called benthos and include microorganis... | Benthic zone | Wikipedia | 464 | 906890 | https://en.wikipedia.org/wiki/Benthic%20zone | Physical sciences | Oceanography | Earth science |
Lakes
As with oceans, the benthic zone is the floor of the lake, composed of accumulated sunken organic matter. The littoral zone is the zone bordering the shore; light penetrates easily and aquatic plants thrive. The pelagic zone represents the broad mass of water, down as far as the depth to which no light penetrate... | Benthic zone | Wikipedia | 402 | 906890 | https://en.wikipedia.org/wiki/Benthic%20zone | Physical sciences | Oceanography | Earth science |
Nutrient flux
Sources of food for benthic communities can derive from the water column above these habitats in the form of aggregations of detritus, inorganic matter, and living organisms. These aggregations are commonly referred to as marine snow, and are important for the deposition of organic matter, and bacterial c... | Benthic zone | Wikipedia | 492 | 906890 | https://en.wikipedia.org/wiki/Benthic%20zone | Physical sciences | Oceanography | Earth science |
It is not easy to map or observe these organisms and their habitats, and most modern observations are made using remotely operated underwater vehicles (ROVs), and rarely submarines.
Ecological research
Benthic macroinvertebrates have many important ecological functions, such as regulating the flow of materials and ene... | Benthic zone | Wikipedia | 405 | 906890 | https://en.wikipedia.org/wiki/Benthic%20zone | Physical sciences | Oceanography | Earth science |
Ecologists are attempting to understand the relationship between heterogeneity and maintaining biodiversity in aquatic ecosystems. Benthic algae has been used as an inherently good subject for studying short term changes and community responses to heterogeneous conditions in streams. Understanding the potential mechani... | Benthic zone | Wikipedia | 233 | 906890 | https://en.wikipedia.org/wiki/Benthic%20zone | Physical sciences | Oceanography | Earth science |
A hair iron or hair tong is a tool used to change the arrangement of the hair using heat. There are three general kinds: curling irons, used to make the hair curl; straightening irons, commonly called straighteners or flat irons, used to straighten the hair; and crimping irons, used to create crimps of the desired size... | Hair iron | Wikipedia | 494 | 908032 | https://en.wikipedia.org/wiki/Hair%20iron | Technology | Household appliances | null |
Early hair straightening systems relied on harsh chemicals that tended to damage the hair. In the 1870s, the French hairdresser Marcel Grateau introduced heated metal hair care implements such as hot combs to straighten hair. Madame C.J. Walker used combs with wider teeth and popularized their use together with her sys... | Hair iron | Wikipedia | 298 | 908032 | https://en.wikipedia.org/wiki/Hair%20iron | Technology | Household appliances | null |
Nanoelectromechanical systems (NEMS) are a class of devices integrating electrical and mechanical functionality on the nanoscale. NEMS form the next logical miniaturization step from so-called microelectromechanical systems, or MEMS devices. NEMS typically integrate transistor-like nanoelectronics with mechanical actua... | Nanoelectromechanical systems | Wikipedia | 440 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
NEMS
In 2000, the first very-large-scale integration (VLSI) NEMS device was demonstrated by researchers at IBM. Its premise was an array of AFM tips which can heat/sense a deformable substrate in order to function as a memory device (Millipede memory). Further devices have been described by Stefan de Haan. In 2007, th... | Nanoelectromechanical systems | Wikipedia | 457 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Carbon allotropes
Many of the commonly used materials for NEMS technology have been carbon based, specifically diamond, carbon nanotubes and graphene. This is mainly because of the useful properties of carbon based materials which directly meet the needs of NEMS. The mechanical properties of carbon (such as large Young... | Nanoelectromechanical systems | Wikipedia | 446 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. They can be considered a rolled up graphene. When rolled at specific and discrete ("chiral") angles, and the combination of the rolling angle and radius decides whether the nanotube has a bandgap (semiconducting) or no bandgap (metallic)... | Nanoelectromechanical systems | Wikipedia | 368 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Difficulties
Despite all of the useful properties of carbon nanotubes and graphene for NEMS technology, both of these products face several hindrances to their implementation. One of the main problems is carbon's response to real life environments. Carbon nanotubes exhibit a large change in electronic properties when... | Nanoelectromechanical systems | Wikipedia | 496 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
A study conducted by Ohio State researchers compared the adhesion and friction parameters of a single crystal silicon with native oxide layer against PDMS coating. PDMS is a silicone elastomer that is highly mechanically tunable, chemically inert, thermally stable, permeable to gases, transparent, non-fluorescent, bioc... | Nanoelectromechanical systems | Wikipedia | 430 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Researchers from the National University of Singapore invented a polydimethylsiloxane (PDMS)-coated nanoelectromechanical system diaphragm embedded with silicon nanowires (SiNWs) to detect chloroform vapor at room temperature. In the presence of chloroform vapor, the PDMS film on the micro-diaphragm absorbs vapor molec... | Nanoelectromechanical systems | Wikipedia | 389 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Simulations
Computer simulations have long been important counterparts to experimental studies of NEMS devices. Through continuum mechanics and molecular dynamics (MD), important behaviors of NEMS devices can be predicted via computational modeling before engaging in experiments. Additionally, combining continuum and... | Nanoelectromechanical systems | Wikipedia | 465 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Manufacturing
Assessing the reliability of NEMS in early stages of the manufacturing process is essential for yield improvement. Forms of surface forces, such as adhesion and electrostatic forces, are largely dependent on surface topography and contact geometry. Selective manufacturing of nano-textured surfaces reduces... | Nanoelectromechanical systems | Wikipedia | 380 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Material properties are size-dependent. Therefore, analyzing the unique characteristics on NEMS and nano-scale material becomes increasingly important to retaining reliability and long-term stability of NEMS devices. Some mechanical properties, such as hardness, elastic modulus, and bend tests, for nano-materials are d... | Nanoelectromechanical systems | Wikipedia | 478 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Recently, nanowires of chalcogenide glasses have shown to be a key platform to design tunable NEMS owing to the availability of active modulation of Young's modulus.
The global market of NEMS is projected to reach $108.88 million by 2022.
Applications
Nanoelectromechanical relay
Nanoelectromechanical systems mass spe... | Nanoelectromechanical systems | Wikipedia | 238 | 908385 | https://en.wikipedia.org/wiki/Nanoelectromechanical%20systems | Technology | Machinery and tools: General | null |
Interchangeable parts are parts (components) that are identical for practical purposes. They are made to specifications that ensure that they are so nearly identical that they will fit into any assembly of the same type. One such part can freely replace another, without any custom fitting, such as filing. This intercha... | Interchangeable parts | Wikipedia | 413 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
Origins of the modern concept
In the late-18th century, French General Jean-Baptiste Vaquette de Gribeauval promoted standardized weapons in what became known as the after it was issued as a royal order in 1765. (At the time the system focused on artillery more than on muskets or handguns.) One of the accomplishments ... | Interchangeable parts | Wikipedia | 426 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
Between 4th July 1793 and 25th November 1795, the London gunsmith Henry Nock delivered 12,010 'screwless' or 'Duke's' locks to the British Board of Ordnance. These locks were intended to be interchangeable, being manufactured in large volumes in a steam-powered factory using gauges and lathes. Subsequent experiments ha... | Interchangeable parts | Wikipedia | 482 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
Mass production using interchangeable parts was first achieved in 1803 by Marc Isambard Brunel in cooperation with Henry Maudslay and Simon Goodrich, under the management of (and with contributions by) Brigadier-General Sir Samuel Bentham, the Inspector General of Naval Works at Portsmouth Block Mills, Portsmouth Docky... | Interchangeable parts | Wikipedia | 415 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
Eli Terry was using interchangeable parts using a milling machine as early as 1800. Ward Francillon, a horologist, concluded in a study that Terry had already accomplished interchangeable parts as early as 1800. The study examined several of Terry's clocks produced between 1800–1807. The parts were labelled and interch... | Interchangeable parts | Wikipedia | 470 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
Late 19th and early 20th centuries: dissemination throughout manufacturing
Skilled engineers and machinists, many with armoury experience, spread interchangeable manufacturing techniques to other American industries, including clockmakers and sewing machine manufacturers Wilcox and Gibbs and Wheeler and Wilson, who us... | Interchangeable parts | Wikipedia | 402 | 908518 | https://en.wikipedia.org/wiki/Interchangeable%20parts | Technology | Basics_6 | null |
The gums or gingiva (: gingivae) consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health.
Structure
The gums are part of the soft tissue lining of the mouth. They surround the teeth and provide a seal around them. Unlike the ... | Gums | Wikipedia | 423 | 908738 | https://en.wikipedia.org/wiki/Gums | Biology and health sciences | Gastrointestinal tract | Biology |
The marginal gum varies in width from 0.5 to 2.0 mm from the free gingival crest to the attached gingiva. The marginal gingiva follows the scalloped pattern established by the contour of the cementoenamel junction (CEJ) of the teeth. The marginal gingiva has a more translucent appearance than the attached gingiva, yet ... | Gums | Wikipedia | 507 | 908738 | https://en.wikipedia.org/wiki/Gums | Biology and health sciences | Gastrointestinal tract | Biology |
The col varies in depth and width, depending on the expanse of the contacting tooth surfaces. The epithelium covering the col consists of the marginal gum of the adjacent teeth, except that it is nonkeratinized. It is mainly present in the broad interdental gingiva of the posterior teeth, and generally is not present w... | Gums | Wikipedia | 465 | 908738 | https://en.wikipedia.org/wiki/Gums | Biology and health sciences | Gastrointestinal tract | Biology |
Texture
Healthy gums have a firm texture that is resistant to movement, and the surface texture often exhibits surface stippling. Unhealthy gums, on the other hand, are often swollen and less firm. Healthy gums have an orange-peel like texture to it due to the stippling.
Reaction to disturbance
Healthy gums usually h... | Gums | Wikipedia | 329 | 908738 | https://en.wikipedia.org/wiki/Gums | Biology and health sciences | Gastrointestinal tract | Biology |
A Sun-synchronous orbit (SSO), also called a heliosynchronous orbit, is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is an orbit arranged so that it precesses through one complete revolution each ... | Sun-synchronous orbit | Wikipedia | 400 | 909019 | https://en.wikipedia.org/wiki/Sun-synchronous%20orbit | Physical sciences | Orbital mechanics | Astronomy |
Orbital precession
A Sun-synchronous orbit is achieved by having the osculating orbital plane precess (rotate) approximately one degree eastward each day with respect to the celestial sphere to keep pace with the Earth's movement around the Sun. This precession is achieved by tuning the inclination to the altitude of ... | Sun-synchronous orbit | Wikipedia | 467 | 909019 | https://en.wikipedia.org/wiki/Sun-synchronous%20orbit | Physical sciences | Orbital mechanics | Astronomy |
Note that according to this approximation equals −1 when the semi-major axis equals , which means that only lower orbits can be Sun-synchronous. The period can be in the range from 88 minutes for a very low orbit ( = , = 96°) to 3.8 hours ( = , but this orbit would be equatorial, with = 180°). A period longer than 3... | Sun-synchronous orbit | Wikipedia | 270 | 909019 | https://en.wikipedia.org/wiki/Sun-synchronous%20orbit | Physical sciences | Orbital mechanics | Astronomy |
{| class="wikitable" style="text-align:right;"
! Orbits per day
! colspan=2 | Period (h)
! Altitude (km)
! Maximal latitude
! Inclin-ation
|-
| 16 || || = 1:30 || 274 || 83.4° || 96.6°
|-
| 15 || || = 1:36 || 567 || 82.3° || 97.7°
|-
| 14 || || ≈ 1:43 || 894 || 81.0° || 99.0°
|-
| 13 || || ≈ 1:51 || 1262 ||... | Sun-synchronous orbit | Wikipedia | 394 | 909019 | https://en.wikipedia.org/wiki/Sun-synchronous%20orbit | Physical sciences | Orbital mechanics | Astronomy |
Sun-synchronous orbits are mostly selected for Earth observation satellites, with an altitude typically between 600 and over the Earth surface. Even if an orbit remains Sun-synchronous, however, other orbital parameters such as argument of periapsis and the orbital eccentricity evolve, due to higher-order perturbation... | Sun-synchronous orbit | Wikipedia | 210 | 909019 | https://en.wikipedia.org/wiki/Sun-synchronous%20orbit | Physical sciences | Orbital mechanics | Astronomy |
Aerial roots are roots growing above the ground. They are often adventitious, i.e. formed from nonroot tissue. They are found in diverse plant species, including epiphytes such as orchids (Orchidaceae), tropical coastal swamp trees such as mangroves, banyan figs (Ficus subg. Urostigma), the warm-temperate rainforest ra... | Aerial root | Wikipedia | 425 | 909402 | https://en.wikipedia.org/wiki/Aerial%20root | Biology and health sciences | Plant anatomy and morphology: General | Biology |
Pneumatophores
These specialized aerial roots enable plants to breathe air in habitats with waterlogged soil. The roots may grow downward from the stem or upward from typical roots. Some botanists classify them as aerating roots rather than aerial roots if they emerge from the soil. The surface of these roots is covere... | Aerial root | Wikipedia | 436 | 909402 | https://en.wikipedia.org/wiki/Aerial%20root | Biology and health sciences | Plant anatomy and morphology: General | Biology |
Pumping and physiology
Aerial roots may receive water and nutrient intake from the air. There are many types of aerial roots; some, such as mangrove, are used for aeration and not for water absorption. In other cases, they are used mainly for structure, and in order to reach the surface. Many plants rely on the leaf sy... | Aerial root | Wikipedia | 496 | 909402 | https://en.wikipedia.org/wiki/Aerial%20root | Biology and health sciences | Plant anatomy and morphology: General | Biology |
The presence of aerial roots is not an indicator of plant health. If a plant does not have aerial roots, that is no reason for concern. | Aerial root | Wikipedia | 29 | 909402 | https://en.wikipedia.org/wiki/Aerial%20root | Biology and health sciences | Plant anatomy and morphology: General | Biology |
A jackhammer (pneumatic drill or demolition hammer in British English) is a pneumatic or electro-mechanical tool that combines a hammer directly with a chisel. It was invented by William McReavy, who then sold the patent to Charles Brady King. Hand-held jackhammers are generally powered by compressed air, but some are ... | Jackhammer | Wikipedia | 508 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
The demand for pneumatic drills was driven especially by miners and tunnelers because steam engines needed fires to operate and the ventilation in mines and tunnels was inadequate to vent the fires' fumes. As well, mines and tunnels might contain flammable explosive gases such as methane. There was also no way to conve... | Jackhammer | Wikipedia | 495 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
In Britain, electromechanical versions are colloquially known by the name of "Kangos". The term comes from the former British brand name now owned by Milwaukee tools.
Additionally, the terms drill and breaker (demolition hammer) are non-interchangeable and refer to two differing distinct types of jackhammer (regardles... | Jackhammer | Wikipedia | 489 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
Modern versions use rotary screw compressors and have more sophisticated variable governors. The unit is usually mounted on a trailer and sometimes includes an electrical generator to supply lights or electric power tools.
Additionally, some users of pneumatic jackhammers may use a pneumatic lubricator which is placed... | Jackhammer | Wikipedia | 428 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
A hydraulic breaker may be fitted to heavy equipment such as an excavator or backhoe, and is widely used for roadwork, quarrying, construction sitework, and general demolition. These larger machine mounted breakers are known as rig mounted, or machine mounted breakers. Such tools can be used horizontally, as they do n... | Jackhammer | Wikipedia | 437 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
The sound of the hammer blows, combined with the explosive air exhaust, makes pneumatic jackhammers dangerously loud, emitting more than 120 dB SPL near the operator’s ears. Sound-blocking earmuffs and earplugs must be worn by the operator to prevent a form of hearing loss, of which tinnitus is the main symptom. Althou... | Jackhammer | Wikipedia | 344 | 910155 | https://en.wikipedia.org/wiki/Jackhammer | Technology | Hydraulics and pneumatics | null |
A warehouse is a building for storing goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial parks on the outskirts of cities, towns, or villages.
Warehouses usually have loading docks to load and unload g... | Warehouse | Wikipedia | 486 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
The need for a warehouse implies having quantities of goods too big to be stored in a domestic storeroom. But as attested by legislation concerning the levy of duties, some medieval merchants across Europe commonly kept goods in their large household storerooms, often on the ground floor or cellars. An example is the F... | Warehouse | Wikipedia | 478 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
Technological innovations of the early 19th century changed the shape of warehouses and the work performed inside them: cast iron columns and later, moulded steel posts; saw-tooth roofs; and steam power. All (except steel) were adopted quickly and were in common use by the middle of the 19th century.
Strong, slender c... | Warehouse | Wikipedia | 434 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
The forklift truck was invented in the early 20th century and came into wide use after World War II. Forklifts transformed the possibilities of multi-level pallet racking of goods in taller, single-level steel-framed buildings for higher storage density. The forklift, and its load fixed to a uniform pallet, enabled the... | Warehouse | Wikipedia | 463 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
These displayed goods for the home trade. This would be finished goods- such as the latest cotton blouses or fashion items. Their street frontage was impressive, so they took the styles of Italianate Palazzi. Warehouses are now more technologically oriented and help in linking stocks with the retail store in an accurat... | Warehouse | Wikipedia | 501 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
The temperature necessary for preservation depends on the storage time required and the type of product. In general, there are three groups of products, foods that are alive (e.g. fruits and vegetables), foods that are no longer alive and have been processed in some form (e.g. meat and fish products), and commodities t... | Warehouse | Wikipedia | 505 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
The fundamental business operations in overseas warehouses include the following:
1. Sellers send bulk products from their home country to an overseas warehouse where the staff undertakes inventory and shelving. When a buyer places an order, the seller sends delivery instructions to the warehouse system and local deli... | Warehouse | Wikipedia | 461 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
The London Warehouse Picadilly was one of four warehouses built by the Manchester, Sheffield and Lincolnshire Railway in about 1865 to service the new London Road Station. It had its own branch to the Ashton Canal. This warehouse was built of brick with stone detailing. It had cast iron columns with wrought iron beams.... | Warehouse | Wikipedia | 481 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
Receiving of goods
Cross-docking of goods
Organizing and storing inventory
Attaching asset tracking solutions (like barcodes) to assets and inventory
Integrating and maintaining a tracking software, like a warehouse management system
Overseeing the integration of new technology
Selecting picking routes
Establish... | Warehouse | Wikipedia | 458 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
Material direction and tracking in a warehouse can be coordinated by a Warehouse Management System (WMS), a database driven computer program. The development of work procedures goes hard in hand with training warehouse personnel. Most firms implement a WMS to standardize work procedure and encourage best practice. Thes... | Warehouse | Wikipedia | 482 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
To help speed up the receiving of goods, Radio-frequency identification (RFID) portals have been installed at the doors of the warehouses for instant verification of product information like the SKUs and their quantities. RFID technology also ensures precise inventory management and easy goods and equipment tracking.
... | Warehouse | Wikipedia | 450 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
Education
There are several non-profit organizations which are focused on imparting knowledge, education and research in the field of warehouse management and its role in the supply chain industry. The Warehousing Education and Research Council (WERC) and International Warehouse Logistics Association (IWLA) in Illinoi... | Warehouse | Wikipedia | 295 | 549146 | https://en.wikipedia.org/wiki/Warehouse | Technology | Commercial buildings | null |
Dracaena () is a genus of about 200 species of trees and succulent shrubs. The formerly accepted genera Pleomele and Sansevieria are now included in Dracaena. In the APG IV classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae (formerly the family Ruscaceae). It has also formerly been s... | Dracaena (plant) | Wikipedia | 375 | 549468 | https://en.wikipedia.org/wiki/Dracaena%20%28plant%29 | Biology and health sciences | Asparagales | Plants |
Dracaena aethiopica (Thunb.) Byng & Christenh.
Dracaena afromontana Mildbr.
Dracaena aletriformis (Haw.) Bos (syn. D. latifolia)
Dracaena americana Donn.Sm. – Central America dragon tree
Dracaena angolensis (Welw. ex Carrière) Byng & Christenh.
Dracaena angustifolia (Medik.) Roxb.
Dracaena arborea (Willd.) Link
... | Dracaena (plant) | Wikipedia | 504 | 549468 | https://en.wikipedia.org/wiki/Dracaena%20%28plant%29 | Biology and health sciences | Asparagales | Plants |
Dracaena kaweesakii Wilkin & Suksathan
Dracaena konaensis (H.St.John) Jankalski
Dracaena malawiana Byng & Christenh.
Dracaena mannii Baker
Dracaena masoniana (Chahin.) Byng & Christenh.
Dracaena ombet Heuglin ex Kotschy & Peyr. – Gabal Elba dragon tree
Dracaena ovata Ker Gawl.
Dracaena pearsonii (N.E.Br.) Byng &... | Dracaena (plant) | Wikipedia | 450 | 549468 | https://en.wikipedia.org/wiki/Dracaena%20%28plant%29 | Biology and health sciences | Asparagales | Plants |
Formerly regarded as dracaena
Asparagus asparagoides (L.) Druce (as D. medeoloides L.f.)
Cordyline australis (G.Forst.) Endl. (as D. australis G.Forst.)
Cordyline fruticosa (L.) A.Chev. (as D. terminalis Lam.)
Cordyline indivisa (G.Forst.) Steud. (as D. indivisa G.Forst.)
Cordyline obtecta (Graham) Baker (as D. o... | Dracaena (plant) | Wikipedia | 456 | 549468 | https://en.wikipedia.org/wiki/Dracaena%20%28plant%29 | Biology and health sciences | Asparagales | Plants |
Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails (marine gastropod mollusks) that, over evolutionary time, have either entirely lost their shells or have seemingly lost their shells... | Sea slug | Wikipedia | 454 | 549472 | https://en.wikipedia.org/wiki/Sea%20slug | Biology and health sciences | Gastropods | Animals |
Nudibranchs (clade Nudibranchia) are a large group of marine gastropods that have no shell at all. These may be the most familiar sort of sea slug. Although most nudibranchs are not large, they are often very eye-catching because so many species have brilliant coloration. In addition to nudibranchs, a number of other t... | Sea slug | Wikipedia | 493 | 549472 | https://en.wikipedia.org/wiki/Sea%20slug | Biology and health sciences | Gastropods | Animals |
The lettuce sea slug (Elysia crispata) has lettuce-like ruffles that line its body. This slug, like other Sacoglossa, uses kleptoplasty, a process in which the slug absorbs chloroplasts from the algae it eats, and uses "stolen" cells to photosynthesize sugars. The ruffles of the lettuce sea slug increase the slug's sur... | Sea slug | Wikipedia | 289 | 549472 | https://en.wikipedia.org/wiki/Sea%20slug | Biology and health sciences | Gastropods | Animals |
Within the field of geology, Bowen's reaction series is the work of the Canadian petrologist Norman L. Bowen, who summarized, based on experiments and observations of natural rocks, the sequence of crystallization of common silicate minerals from typical basaltic magma undergoing fractional crystallization (i.e. crysta... | Bowen's reaction series | Wikipedia | 511 | 550104 | https://en.wikipedia.org/wiki/Bowen%27s%20reaction%20series | Physical sciences | Petrology | Earth science |
In the theory of partial differential equations, elliptic operators are differential operators that generalize the Laplace operator. They are defined by the condition that the coefficients of the highest-order derivatives be positive, which implies the key property that the principal symbol is invertible, or equivale... | Elliptic operator | Wikipedia | 486 | 550137 | https://en.wikipedia.org/wiki/Elliptic%20operator | Mathematics | Differential equations | null |
Let L be an elliptic operator of order 2k with coefficients having 2k continuous derivatives. The Dirichlet problem for L is to find a function u, given a function f and some appropriate boundary values, such that Lu = f and such that u has the appropriate boundary values and normal derivatives. The existence theory fo... | Elliptic operator | Wikipedia | 485 | 550137 | https://en.wikipedia.org/wiki/Elliptic%20operator | Mathematics | Differential equations | null |
Properties
For L as in Example 2 on U, which is an open domain with C1 boundary, then there is a number γ>0 such that for each μ>γ, satisfies the assumptions of Lax–Milgram lemma.
Invertibility: For each μ>γ, admits a compact inverse.
Eigenvalues and eigenvectors: If A is symmetric, bi,c are zero, then (1) Eigen... | Elliptic operator | Wikipedia | 497 | 550137 | https://en.wikipedia.org/wiki/Elliptic%20operator | Mathematics | Differential equations | null |
Riftia pachyptila, commonly known as the giant tube worm and less commonly known as the giant beardworm, is a marine invertebrate in the phylum Annelida (formerly grouped in phylum Pogonophora and Vestimentifera) related to tube worms commonly found in the intertidal and pelagic zones. R. pachyptila lives on the floor... | Riftia | Wikipedia | 346 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
Development
R. pachyptila develops from a free-swimming, pelagic, nonsymbiotic trochophore larva, which enters juvenile (metatrochophore) development, becoming sessile, and subsequently acquiring symbiotic bacteria. The symbiotic bacteria, on which adult worms depend for sustenance, are not present in the gametes, but ... | Riftia | Wikipedia | 444 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
In the middle part, the trunk or third body region, is full of vascularized solid tissue, and includes body wall, gonads, and the coelomic cavity. Here is located also the trophosome, spongy tissue where a billion symbiotic, thioautotrophic bacteria and sulfur granules are found. Since the mouth, digestive system, and... | Riftia | Wikipedia | 407 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
Symbiosis
The discovery of bacterial invertebrate chemoautotrophic symbiosis, particularly in vestimentiferan tubeworms R. pachyptila and then in vesicomyid clams and mytilid mussels revealed the chemoautotrophic potential of the hydrothermal vent tube worm. Scientists discovered a remarkable source of nutrition that ... | Riftia | Wikipedia | 398 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
Initial evidence for a chemoautotrophic symbiosis in R. pachyptila came from microscopic and biochemical analyses showing Gram-negative bacteria packed within a highly vascularized organ in the tubeworm trunk called the trophosome. Additional analyses involving stable isotope, enzymatic, and physiological characteriza... | Riftia | Wikipedia | 508 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
Evidence based on 16S rRNA analysis affirms that R. pachyptila chemoautotrophic bacteria belong to two different clades: Gammaproteobacteria and Campylobacterota (e.g. Sulfurovum riftiae) that get energy from the oxidation of inorganic sulfur compounds such as hydrogen sulfide (H2S, HS−, S2-) to synthesize ATP for carb... | Riftia | Wikipedia | 439 | 550334 | https://en.wikipedia.org/wiki/Riftia | Biology and health sciences | Lophotrochozoa | Animals |
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