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In most telecommunications organizations, a virtual channel is a method of remapping the program number as used in H.222 Program Association Tables and Program Mapping Tables to a channel number that can be entered as digits on a receiver's remote control. Often, virtual channels are implemented in digital television to help users to go to channels easily and in general to ease the transition from analogue to digital broadcasting. Assigning virtual channels is most common in parts of the world where TV stations were colloquially named after the RF channel they were transmitting on ("Channel 6 Springfield"), as was common in North America during the analogue TV era. In other parts of the world, such as Europe, virtual channels are rarely used or needed, because TV stations there identify themselves by name, not by RF channel or callsign. | https://en.wikipedia.org/wiki/Virtual_channel |
A "virtual channel" was first used for DigiCipher 2 in North America. It was later called a logical channel number (LCN) and used for private European Digital Video Broadcasting extensions widely used by the NDS Group and by NorDig in other markets. Pay television operators were the first to use these systems for channel reassignment and rearrangement to meet their need to group channels by their content or origin and, to a lesser extent, to localize advertising. | https://en.wikipedia.org/wiki/Virtual_channel |
Free-to-air stations using Advanced Television Systems Committee standards (ATSC) used the same television frequency channel allocation that the NTSC channel was using when both were simulcasting. They achieved this by the DigiCipher 2 method. | https://en.wikipedia.org/wiki/Virtual_channel |
Viewers could then use the same number to bring up either service. Free-to-air DVB network operators, such as DTV Services Ltd. (d.b.a. Freeview) and Freeview New Zealand Ltd., use the NorDig method and follow the same practice as pay-TV operators. The exception is Freeview Australia Ltd., which also use the NorDig method and partly follow the ATSC practice of using the same VHF radio-frequency channel allocation that the PAL channel is simulcasting on from the metropolitan station's main transmission point (i2, 7, 9, and 10) with the major and minor format emulated by multiplying by ten. | https://en.wikipedia.org/wiki/Virtual_channel |
In most territories, access to mobile satellite service is managed by traditional telecom companies and specialized resellers which market hardware, software and network access to end users, although occasionally some constellation operators also market service directly to end users. Some companies providing commercial access: Avanti Globalsat Group Iridium Communications Inmarsat Telespazio Thuraya Vizada | https://en.wikipedia.org/wiki/Mobile-satellite_service |
In most texts on statistical mechanics the statistical distribution functions f {\displaystyle f} in Maxwell–Boltzmann statistics, Bose–Einstein statistics, Fermi–Dirac statistics) are derived by determining those for which the system is in its state of maximum probability. But one really requires those with average or mean probability, although – of course – the results are usually the same for systems with a huge number of elements, as is the case in statistical mechanics. The method for deriving the distribution functions with mean probability has been developed by C. G. Darwin and Fowler and is therefore known as the Darwin–Fowler method. This method is the most reliable general procedure for deriving statistical distribution functions. | https://en.wikipedia.org/wiki/Darwin–Fowler_method |
Since the method employs a selector variable (a factor introduced for each element to permit a counting procedure) the method is also known as the Darwin–Fowler method of selector variables. Note that a distribution function is not the same as the probability – cf. Maxwell–Boltzmann distribution, Bose–Einstein distribution, Fermi–Dirac distribution. Also note that the distribution function f i {\displaystyle f_{i}} which is a measure of the fraction of those states which are actually occupied by elements, is given by f i = n i / g i {\displaystyle f_{i}=n_{i}/g_{i}} or n i = f i g i {\displaystyle n_{i}=f_{i}g_{i}} , where g i {\displaystyle g_{i}} is the degeneracy of energy level i {\displaystyle i} of energy ε i {\displaystyle \varepsilon _{i}} and n i {\displaystyle n_{i}} is the number of elements occupying this level (e.g. in Fermi–Dirac statistics 0 or 1). | https://en.wikipedia.org/wiki/Darwin–Fowler_method |
Total energy E {\displaystyle E} and total number of elements N {\displaystyle N} are then given by E = ∑ i n i ε i {\displaystyle E=\sum _{i}n_{i}\varepsilon _{i}} and N = ∑ n i {\displaystyle N=\sum n_{i}} . The Darwin–Fowler method has been treated in the texts of E. Schrödinger, Fowler and Fowler and E. A. Guggenheim, of K. Huang, and of H. J. W. Müller–Kirsten. The method is also discussed and used for the derivation of Bose–Einstein condensation in the book of R. B. Dingle. | https://en.wikipedia.org/wiki/Darwin–Fowler_method |
In most theories of this state, it is supposed that vacancies – empty sites normally occupied by particles in an ideal crystal – lead to supersolidity. These vacancies are caused by zero-point energy, which also causes them to move from site to site as waves. Because vacancies are bosons, if such clouds of vacancies can exist at very low temperatures, then a Bose–Einstein condensation of vacancies could occur at temperatures less than a few tenths of a Kelvin. | https://en.wikipedia.org/wiki/Supersolid |
A coherent flow of vacancies is equivalent to a "superflow" (frictionless flow) of particles in the opposite direction. Despite the presence of the gas of vacancies, the ordered structure of a crystal is maintained, although with less than one particle on each lattice site on average. Alternatively, a supersolid can also emerge from a superfluid. In this situation, which is realised in the experiments with atomic Bose–Einstein condensates, the spatially ordered structure is a modulation on top of the superfluid density distribution. | https://en.wikipedia.org/wiki/Supersolid |
In most theories up to the eighteenth century, light was pictured as being made up of particles. Since particle models cannot easily account for the refraction, diffraction and birefringence of light, wave theories of light were proposed by René Descartes (1637), Robert Hooke (1665), and Christiaan Huygens (1678); however, particle models remained dominant, chiefly due to the influence of Isaac Newton. In the early 19th century, Thomas Young and August Fresnel clearly demonstrated the interference and diffraction of light, and by 1850 wave models were generally accepted. James Clerk Maxwell's 1865 prediction that light was an electromagnetic wave – which was confirmed experimentally in 1888 by Heinrich Hertz's detection of radio waves – seemed to be the final blow to particle models of light. | https://en.wikipedia.org/wiki/Photon |
The Maxwell wave theory, however, does not account for all properties of light. The Maxwell theory predicts that the energy of a light wave depends only on its intensity, not on its frequency; nevertheless, several independent types of experiments show that the energy imparted by light to atoms depends only on the light's frequency, not on its intensity. For example, some chemical reactions are provoked only by light of frequency higher than a certain threshold; light of frequency lower than the threshold, no matter how intense, does not initiate the reaction. | https://en.wikipedia.org/wiki/Photon |
Similarly, electrons can be ejected from a metal plate by shining light of sufficiently high frequency on it (the photoelectric effect); the energy of the ejected electron is related only to the light's frequency, not to its intensity.At the same time, investigations of black-body radiation carried out over four decades (1860–1900) by various researchers culminated in Max Planck's hypothesis that the energy of any system that absorbs or emits electromagnetic radiation of frequency ν is an integer multiple of an energy quantum E = hν . As shown by Albert Einstein, some form of energy quantization must be assumed to account for the thermal equilibrium observed between matter and electromagnetic radiation; for this explanation of the photoelectric effect, Einstein received the 1921 Nobel Prize in physics.Since the Maxwell theory of light allows for all possible energies of electromagnetic radiation, most physicists assumed initially that the energy quantization resulted from some unknown constraint on the matter that absorbs or emits the radiation. In 1905, Einstein was the first to propose that energy quantization was a property of electromagnetic radiation itself. | https://en.wikipedia.org/wiki/Photon |
Although he accepted the validity of Maxwell's theory, Einstein pointed out that many anomalous experiments could be explained if the energy of a Maxwellian light wave were localized into point-like quanta that move independently of one another, even if the wave itself is spread continuously over space. In 1909 and 1916, Einstein showed that, if Planck's law regarding black-body radiation is accepted, the energy quanta must also carry momentum p = h / λ , making them full-fledged particles. This photon momentum was observed experimentally by Arthur Compton, for which he received the Nobel Prize in 1927. | https://en.wikipedia.org/wiki/Photon |
The pivotal question then, was how to unify Maxwell's wave theory of light with its experimentally observed particle nature? The answer to this question occupied Albert Einstein for the rest of his life, and was solved in quantum electrodynamics and its successor, the Standard Model. (See § Quantum field theory and § As a gauge boson, below.) | https://en.wikipedia.org/wiki/Photon |
Einstein's 1905 predictions were verified experimentally in several ways in the first two decades of the 20th century, as recounted in Robert Millikan's Nobel lecture. However, before Compton's experiment showed that photons carried momentum proportional to their wave number (1922), most physicists were reluctant to believe that electromagnetic radiation itself might be particulate. | https://en.wikipedia.org/wiki/Photon |
(See, for example, the Nobel lectures of Wien, Planck and Millikan.) Instead, there was a widespread belief that energy quantization resulted from some unknown constraint on the matter that absorbed or emitted radiation. | https://en.wikipedia.org/wiki/Photon |
Attitudes changed over time. In part, the change can be traced to experiments such as those revealing Compton scattering, where it was much more difficult not to ascribe quantization to light itself to explain the observed results.Even after Compton's experiment, Niels Bohr, Hendrik Kramers and John Slater made one last attempt to preserve the Maxwellian continuous electromagnetic field model of light, the so-called BKS theory. An important feature of the BKS theory is how it treated the conservation of energy and the conservation of momentum. | https://en.wikipedia.org/wiki/Photon |
In the BKS theory, energy and momentum are only conserved on the average across many interactions between matter and radiation. However, refined Compton experiments showed that the conservation laws hold for individual interactions. Accordingly, Bohr and his co-workers gave their model "as honorable a funeral as possible". | https://en.wikipedia.org/wiki/Photon |
Nevertheless, the failures of the BKS model inspired Werner Heisenberg in his development of matrix mechanics.A few physicists persisted in developing semiclassical models in which electromagnetic radiation is not quantized, but matter appears to obey the laws of quantum mechanics. Although the evidence from chemical and physical experiments for the existence of photons was overwhelming by the 1970s, this evidence could not be considered as absolutely definitive; since it relied on the interaction of light with matter, and a sufficiently complete theory of matter could in principle account for the evidence. Nevertheless, all semiclassical theories were refuted definitively in the 1970s and 1980s by photon-correlation experiments. Hence, Einstein's hypothesis that quantization is a property of light itself is considered to be proven. | https://en.wikipedia.org/wiki/Photon |
In most three electrode experiments there are two isolated cells. One contains the auxiliary and working electrode, while the other contains the reference electrode. Strictly speaking, the reference electrode does not require a separate compartment. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
A Quasi-Reference Electrode such as a silver/silver chloride wire electrode can be exposed directly to the analyte solution. In such situations there is concern that the analyte and trace redox products may interact with the reference electrode and either render it useless or increase drift. As a result, even these simple references are commonly sequestered in their own cells. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
The more complex references such as standard hydrogen electrode, saturated calomel electrode, or silver chloride electrode(specific concentration) can not directly mix the analyte solution for fear the electrode will fall apart or interact/react with the analyte. A bulk electrolysis is best performed in a three part cell in which both the auxiliary electrode and reference electrode have their own cell which connects to the cell containing the working electrode. This isolates the undesired redox events taking place at the auxiliary electrode. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
During bulk electrolysis, the analyte undergoes a redox event at the working electrode. If the system was open, then it would be possible for the product of that reaction to diffuse back to the auxiliary electrode and undergo the inverse redox reaction. In addition to maintaining the proper current at the working electrode, the auxiliary electrode will experience extreme potentials often oxidizing or reducing the solvent or electrolyte to balance the current. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
In voltammetry experiments, the currents (amps) are so small and it is not a problem to decompose a small amount of solvent or electrolyte. In contrast, a bulk electrolysis involves currents greater by several orders of magnitude. At the auxiliary electrode, this greater current would decompose a significant amount of the solution/electrolyte and probably boiling the solution in the process all in an effort to balance the current. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
To mitigate this challenge the auxiliary cell will often contain a stoichiometric or greater amount of sacrificial reductant (ferrocene) or sacrificial oxidant (ferrocenium) to balance the overall redox reaction. For ideal performance the auxiliary electrode should be similar in surface area, as close as possible, and evenly spaced with the working electrode. This is in an effort to prevent "hot spots". | https://en.wikipedia.org/wiki/Bulk_electrolysis |
Hot spots are the result of current following the path of least resistance. This means much of the redox chemistry will occur at the points at either end of the shortest path between the working and auxiliary electrode. Heating associated with the capacitances resistance of the solution can occur at the area around these points, actually boiling the solution. The bubbling resulting from this isolated boiling of the solution can be confused with gas evolution. | https://en.wikipedia.org/wiki/Bulk_electrolysis |
In most tile-matching games, players obtain points for each match. Higher scores are awarded for more difficult matches, such as those involving a greater number of similar tiles. In some tile games, when tiles are matched and removed, pieces above them fall to fill the space (as with Bejeweled and Candy Crush Saga). This creates the potential for additional matches and creating scoring combos, with all subsequent matches scored at higher point values. | https://en.wikipedia.org/wiki/Tile-matching_video_game |
In most traditional PCRs the resulting products are analyzed after the PCR has been completed. This is called end-point analysis and is normally qualitative of nature rather than being quantitative. For this sort of analysis, products are mostly analyzed on an agarose gel and visualized using ethidium bromide as a fluorescent dye. Direct correlation between signal strength and initial sample concentration is not possible using end-point analysis since PCR efficiency decreases as the reaction nears the plateau phase. | https://en.wikipedia.org/wiki/Potato_virus_Y |
Quantitative PCR, however, offers an accurate and rapid alternative to traditional PCR. Quantitative PCR offers the researcher the opportunity to amplify and analyze the product in a single tube using fluorescent dyes. This is known as homogeneous PCR. | https://en.wikipedia.org/wiki/Potato_virus_Y |
During a quantitative PCR the increase in fluorescence is correlated with the increase in product. Through the use of different specific, dyes quantitative PCR can be used to distinguish between different strains of a virus and even to detect point mutations. | https://en.wikipedia.org/wiki/Potato_virus_Y |
The major advantage of quantitative PCR is that analysis of resulting products using gel electrophoresis is not required. This means that quantitative PCR can be implemented as a high-throughput technique for sample screening. Quantitative PCR has been described for detection and discrimination of PVYO and PVYN isolates and for reliable discrimination between PVYNTN and PVYN isolates. | https://en.wikipedia.org/wiki/Potato_virus_Y |
In most traditional fighter kite manufacture, the skins of kites are made from a lightweight thin paper and the spars are usually made from a lightweight and flexible wood, usually bamboo. In modern American fighters, the kite skins are made from a variety of synthetic materials – mylar, aircraft insulation (orcon or insulfab), nylon, and polyester sheeting. The spine may still be bamboo, but often along with the bow is constructed of fiberglass or carbon fibre. | https://en.wikipedia.org/wiki/Fighter_kite |
In most trains, a basic level of protection is provided by a "dead man's handle" or pedal. If the driver is taken ill and releases this, the power will be shut off and an emergency brake application will be initiated to stop the train. More recent safety standards do not consider this to be adequate, as the driver may slump over the dead man's handle and continue to hold it down even though they are not capable of controlling the train. Modern trains overcome this risk with the addition of a vigilance system to the dead man's system. | https://en.wikipedia.org/wiki/Vigilance_control |
A buzzer or bell sounds every minute or so in order to alert the motorman or engineer. If they do not respond by moving a controller, or releasing and then re-applying the dead man's handle, the system will automatically initiate an emergency brake application. Most major rail systems in the world use this equipment, both in their freight and passenger operations. It is also used on the R143 and other New York City Subway cars while under CBTC operation. In the US, older locomotives produced before 1995 do not carry this feature, but given the modular nature of the system it is not uncommon to find them retrofitted. | https://en.wikipedia.org/wiki/Vigilance_control |
In most treatments of OLS, the regressors (parameters of interest) in the design matrix X {\displaystyle \mathbf {X} } are assumed to be fixed in repeated samples. This assumption is considered inappropriate for a predominantly nonexperimental science like econometrics. Instead, the assumptions of the Gauss–Markov theorem are stated conditional on X {\displaystyle \mathbf {X} } . | https://en.wikipedia.org/wiki/Gauss–Markov_model |
In most tropical cyclone basins, use of the satellite-based Dvorak technique is the primary method used to determine a tropical cyclone's maximum sustained winds. The extent of spiral banding and difference in temperature between the eye and eyewall is used within the technique to assign a maximum sustained wind and pressure. Central pressure values for their centers of low pressure are approximate. | https://en.wikipedia.org/wiki/Maximum_sustained_winds |
The intensity of example hurricanes is derived from both the time of landfall and the maximum intensity. The tracking of individual clouds on minutely satellite imagery could be used in the future in estimating surface winds speeds for tropical cyclones.Ship and land observations are also used, when available. In the Atlantic as well as the Central and Eastern Pacific basins, reconnaissance aircraft are still utilized to fly through tropical cyclones to determine flight level winds, which can then be adjusted to provide a fairly reliable estimate of maximum sustained winds. A reduction of 10 percent of the winds sampled at flight level is used to estimate the maximum sustained winds near the surface, which has been determined during the past decade through the use of GPS dropwindsondes. Doppler weather radar can be used in the same manner to determine surface winds with tropical cyclones near land. | https://en.wikipedia.org/wiki/Maximum_sustained_winds |
In most types of strategy games, the player needs particular buildings in order to research specific technologies or build specific advanced units (StarCraft, Total Annihilation), while in other games upgrades/technologies are unlocked through research of their parent technology research (Warzone 2100). In many TBS games the prerequisite is one or more lower-level technologies, with no dependency on specific buildings (Master of Orion series, Civilization series, Space Empires series). Most strategy games however use both systems. both requiring dedicated buildings and in advanced cases pre requisite technology, sometimes culminating in a game ending super-weapon of some kind. | https://en.wikipedia.org/wiki/Technology_tree |
In most typographic designs, the slash of a slashed zero usually does not extend past the ellipse. Compare this to the Scandinavian vowel "Ø", the "empty set" symbol "∅" and the diameter symbol ⌀. A convention common on early line printers left zero unornamented but added a tail or hook to the letter-O so that it resembled an inverted Q (like U+213A ℺) or cursive capital letter-O ( O {\displaystyle \,{\mathcal {O}}\,} ).In the Fixedsys typeface, the numeral 0 has two internal barbs along the lines of the slash. This appears much like a white "S" within the black borders of the zero. In the FE-Schrift typeface, used on German car license plates, the zero is rectangular and has an "insinuated" slash: a diagonal crack just beneath the top right curve. | https://en.wikipedia.org/wiki/Slashed_zero |
In most uses of en dashes, such as when used in indicating ranges, they are closed up to the joined words. It is only when en dashes are used in setting off parenthetical expressions – such as this one – that they take spaces around them. For more on the choice of em versus en in this context, see En dash versus em dash. | https://en.wikipedia.org/wiki/Em_dash |
In most variants of the dual-slope integrating converter, the converter's performance is dependent on one or more of the circuit parameters. In the case of the basic design, the output of the converter is in terms of the reference voltage. In more advanced designs, there are also dependencies on one or more resistors used in the circuit or on the integrator capacitor being used. In all cases, even using expensive precision components there may be other effects that are not accounted for in the general dual-slope equations (dielectric effect on the capacitor or frequency or temperature dependencies on any of the components). | https://en.wikipedia.org/wiki/Integrating_ADC |
Any of these variations result in error in the output of the converter. In the best case, this is simply gain and/or offset error. In the worst case, nonlinearity or nonmonotonicity could result. | https://en.wikipedia.org/wiki/Integrating_ADC |
Some calibration can be performed internal to the converter (i.e., not requiring any special external input). This type of calibration would be performed every time the converter is turned on, periodically while the converter is running, or only when a special calibration mode is entered. Another type of calibration requires external inputs of known quantities (e.g., voltage standards or precision resistance references) and would typically be performed infrequently (every year for equipment used in normal conditions, more often when being used in metrology applications). | https://en.wikipedia.org/wiki/Integrating_ADC |
Of these types of error, offset error is the simplest to correct (assuming that there is a constant offset over the entire range of the converter). This is often done internal to the converter itself by periodically taking measurements of the ground potential. Ideally, measuring the ground should always result in a zero output. | https://en.wikipedia.org/wiki/Integrating_ADC |
Any non-zero output indicates the offset error in the converter. That is, if the measurement of ground resulted in an output of 0.001 volts, one can assume that all measurements will be offset by the same amount and can subtract 0.001 from all subsequent results. Gain error can similarly be measured and corrected internally (again assuming that there is a constant gain error over the entire output range). | https://en.wikipedia.org/wiki/Integrating_ADC |
The voltage reference (or some voltage derived directly from the reference) can be used as the input to the converter. If the assumption is made that the voltage reference is accurate (to within the tolerances of the converter) or that the voltage reference has been externally calibrated against a voltage standard, any error in the measurement would be a gain error in the converter. If, for example, the measurement of a converter's 5 volt reference resulted in an output of 5.3 volts (after accounting for any offset error), a gain multiplier of 0.94 (5 / 5.3) can be applied to any subsequent measurement results. | https://en.wikipedia.org/wiki/Integrating_ADC |
In most variations, a 'kitty' of four, five, or six cards is dealt separately from the cards delivered to each player. If no jokers are being used, the kitty will consist of four cards. If one joker is being used, the kitty will consist of five cards. | https://en.wikipedia.org/wiki/Bid_whist |
And if two jokers are being used, the kitty will consist of six cards. The winner of the bid auction can use the kitty. (This is similar to the skat in Skat.) | https://en.wikipedia.org/wiki/Bid_whist |
In most varieties of English, for instance Received Pronunciation and General American, there is allophonic variation in vowel length depending on the value of the consonant that follows it: vowels are shorter before voiceless consonants and are longer when they come before voiced consonants. Thus, the vowel in bad /bæd/ is longer than the vowel in bat /bæt/. Also compare neat with need . The vowel sound in "beat" is generally pronounced for about 190 milliseconds, but the same vowel in "bead" lasts 350 milliseconds in normal speech, the voiced final consonant influencing vowel length. | https://en.wikipedia.org/wiki/Vowel_length |
Cockney English features short and long varieties of the closing diphthong . The short corresponds to RP /ɔː/ in morphologically closed syllables (see thought split), whereas the long corresponds to the non-prevocalic sequence /ɔːl/ (see l-vocalization). The following are minimal pairs of length: The difference is lost in running speech, so that fault falls together with fort and fought as or . | https://en.wikipedia.org/wiki/Vowel_length |
The contrast between the two diphthongs is phonetic rather than phonemic, as the /l/ can be restored in formal speech: etc., which suggests that the underlying form of is /ˈfoːlt/ (John Wells says that the vowel is equally correctly transcribed with ⟨ɔʊ⟩ or ⟨oʊ⟩, not to be confused with GOAT /ʌʊ/, ). Furthermore, a vocalized word-final /l/ is often restored before a word-initial vowel, so that fall out (cf. thaw out , with an intrusive /r/) is somewhat more likely to contain the lateral than fall . The distinction between and exists only word-internally before consonants other than intervocalic /l/. | https://en.wikipedia.org/wiki/Vowel_length |
In the morpheme-final position only occurs (with the THOUGHT vowel being realized as ), so that all is always distinct from or . Before the intervocalic /l/ is the banned diphthong, though here either of the THOUGHT vowels can occur, depending on morphology (compare falling with aweless ).In cockney, the main difference between /ɪ/ and /ɪə/, /e/ and /eə/ as well as /ɒ/ and /ɔə/ is length, not quality, so that his , merry and Polly differ from here's , Mary and poorly (see cure-force merger) mainly in length. In broad cockney, the contrast between /æ/ and /æʊ/ is also mainly one of length; compare hat with out (cf. the near-RP form , with a wide closing diphthong). | https://en.wikipedia.org/wiki/Vowel_length |
In most vehicles with a manual transmission, the driver selects gears by manipulating a lever called a gear stick (also called a gearshift, gear lever or shifter). In most automobiles, the gear stick is located on the floor between the driver and front passenger, but some cars have a gear stick that is mounted to the steering column or center console. The movement of the gear stick is transferred (via solid linkages or cables) to the selector forks within the transmission. Motorcycles typically employ sequential manual transmissions, although the shift pattern is modified slightly for safety reasons. Gear selection is usually via the left-foot (or, on older motorcycles; right-foot) shift lever with a layout of 1–N–2–3–4–5–6. | https://en.wikipedia.org/wiki/Manual_gearbox |
In most vehicles with rear drum brakes, two emergency brake/parking brake cables actuate the brake drums mechanically, but with much less force than is available through the primary hydraulic brake system. It is common for this type of system to work well when facing downhill but be unable to hold the vehicle stopped without using wheel chocks when facing up a steep hill. An improvement over stock parking brakes is useful for off-road vehicles such as tractors, tow trucks, 4x4's, construction vehicles or any drum brake vehicle on ice or steep terrain. | https://en.wikipedia.org/wiki/Line_lock |
Some manufactures use a transmission brake which locks the entire drivetrain. In order to park by using the primary hydraulic brakes, a hand-operated valve is added to lock hydraulic pressure in the brake line. For parking using the brakes on all four wheels, two valves may be necessary. | https://en.wikipedia.org/wiki/Line_lock |
Any leakage at the brake cylinders will reduce pressure in the line and release the brakes. For this reason, line locks should only be used temporarily. Parking brakes using disc brakes do not have the same issues as drum brakes, but a vehicle needing parking brakes on all four wheels will still benefit from line locks. | https://en.wikipedia.org/wiki/Line_lock |
In most versions of its asterism, the neighbouring bright stars, thus plotted along the imaginary hull forming Carina are Omega Carinae which is approximately 120 light years closer and PP (also known as p) Carinae, of a similar distance to Theta. | https://en.wikipedia.org/wiki/Theta_Carinae |
In most versions of the penetron the tube has an inner layer of red and outer layer of green, separated by a thin dielectric layer. A complete image is produced by scanning twice, once with the gun set to a lower power that is stopped in the red layer, and then again at a higher power that travels through the red layer and into the green. Yellow can be produced by hitting the same location on both sweeps. In a display where the colors are either on or off and various brightness levels do not have to be created, the system can be further simplified by removing the color selection grid and modulating the voltage of the electron gun itself. | https://en.wikipedia.org/wiki/Penetron |
However, this also causes problems because the electrons will reach the screen faster when accelerated with higher voltages, which means that the deflection system has to be increased in power as well to ensure the scanning creates the same screen size and line widths on both passes. Several alternative arrangements of the penetron were experimented on to address this problem. One common attempt used an electron multiplier at the tube face instead of the selection grid. | https://en.wikipedia.org/wiki/Penetron |
In this system a low-energy scanning beam was used, and magnets were set to cause the electrons to strike the sides of the multipliers. A shower of higher-energy electrons would then be released and travel to the layered phosphors of a normal penetron arrangement. It was later noticed that the beams emanating from the multipliers landed in rings, which allowed a new arrangement of phosphors in concentric rings instead of layers.The main advantage to the penetron is that it lacks the mechanical focusing system of a shadow mask television, which means that all of the beam energy reaches the screen. | https://en.wikipedia.org/wiki/Penetron |
For any given amount of power, the penetron will be much brighter, typically 85% brighter. This is a major advantage in an aircraft setting, where power supply is limited but the displays need to be bright enough to be easily read even when directly lit by sunlight. The system is guaranteed to produce the correct colors in spite of external interference or the g-forces of maneuvering – a very important quality in aviation settings. | https://en.wikipedia.org/wiki/Penetron |
The penetron also offered higher resolutions because the phosphor was continuous, as opposed to the small spots in a shadow mask system. Additionally, the lack of the shadow mask makes the penetron much more robust mechanically. Sinclair experimented with a variant of this technology on his early pocket TV screens, but was unable to produce an RGB version. Examples of these tubes exist as prototypes. | https://en.wikipedia.org/wiki/Penetron |
In most vertebrates, digestion is a multistage process in the digestive system, starting from ingestion of raw materials, most often other organisms. Ingestion usually involves some type of mechanical and chemical processing. Digestion is separated into four steps: Ingestion: placing food into the mouth (entry of food in the digestive system), Mechanical and chemical breakdown: mastication and the mixing of the resulting bolus with water, acids, bile and enzymes in the stomach and intestine to break down complex chemical species into simple structures, Absorption: of nutrients from the digestive system to the circulatory and lymphatic capillaries through osmosis, active transport, and diffusion, and Egestion (Excretion): Removal of undigested materials from the digestive tract through defecation.Underlying the process is muscle movement throughout the system through swallowing and peristalsis. Each step in digestion requires energy, and thus imposes an "overhead charge" on the energy made available from absorbed substances. | https://en.wikipedia.org/wiki/Absorptive_state |
Differences in that overhead cost are important influences on lifestyle, behavior, and even physical structures. Examples may be seen in humans, who differ considerably from other hominids (lack of hair, smaller jaws and musculature, different dentition, length of intestines, cooking, etc.). The major part of digestion takes place in the small intestine. | https://en.wikipedia.org/wiki/Absorptive_state |
The large intestine primarily serves as a site for fermentation of indigestible matter by gut bacteria and for resorption of water from digests before excretion. In mammals, preparation for digestion begins with the cephalic phase in which saliva is produced in the mouth and digestive enzymes are produced in the stomach. Mechanical and chemical digestion begin in the mouth where food is chewed, and mixed with saliva to begin enzymatic processing of starches. The stomach continues to break food down mechanically and chemically through churning and mixing with both acids and enzymes. Absorption occurs in the stomach and gastrointestinal tract, and the process finishes with defecation. | https://en.wikipedia.org/wiki/Absorptive_state |
In most vertebrates, the frontal bone is paired, rather than presenting the single, fused structure found in humans (see frontal suture). It typically lies on the upper part of the head, between the eyes, but in many non-mammalian animals it does not form part of the orbital cavity. Instead, in reptiles, bony fish and amphibians it is often separated from the orbits by one or two additional bones not found in mammals. These bones, the prefrontals and postfrontals, together form the upper margin of the eye sockets, and lie to either side of the frontal bones. | https://en.wikipedia.org/wiki/Frontal_bone |
In most vertebrates, the lips are relatively unimportant folds of tissue lying just outside the jaws. However, in mammals, they become much more prominent, being separated from the jaws by a deep cleft (a notable exception being the naked mole-rat, whose lips close behind the front teeth). They are also more mobile in mammals than in other groups since it is only in this group that they have any attached muscles. In some teleost fish, the lips may be modified to carry sensitive barbels. In birds and turtles, the lips are hard and keratinous, forming a solid beak. Clevosaurids like Clevosaurus are notable for the presence of bone "lips"; in these species the tooth-like jaw projections common to all sphenodontians form a beak-like edge around the jaws, protecting the teeth within. | https://en.wikipedia.org/wiki/Lip |
In most vertebrates, the main skeletal component is bone. Bones compose a unique skeletal system for each type of animal. Another important component is cartilage which in mammals is found mainly in the joint areas. In other animals, such as the cartilaginous fishes, which include the sharks, the skeleton is composed entirely of cartilage. | https://en.wikipedia.org/wiki/Skeletal_system |
The segmental pattern of the skeleton is present in all vertebrates, with basic units being repeated, such as in the vertebral column and the ribcage.Bones are rigid organs that form part of the endoskeleton of vertebrates. They provide structural support for the body, assist in movement by opposing muscular contraction, and create a protective wall around internal organs. Bones are primarily made of inorganic minerals, such as hydroxyapatite, while the remainder is made of an organic matrix and water. | https://en.wikipedia.org/wiki/Skeletal_system |
The hollow tubular structure of bones provide considerable resistance against compression while staying lightweight. Most cells in bones are either osteoblasts, osteoclasts, or osteocytes.Bone tissue is a type of dense connective tissue. One of the types of tissue that makes up bone tissue is mineralized tissue and this gives it rigidity and a honeycomb-like three-dimensional internal structure. | https://en.wikipedia.org/wiki/Skeletal_system |
Bones also produce red and white blood cells and serve as calcium and phosphate storage at the cellular level. Other types of tissue found in bones include marrow, endosteum and periosteum, nerves, blood vessels and cartilage. During embryonic development, bones are developed individually from skeletogenic cells in the ectoderm and mesoderm. | https://en.wikipedia.org/wiki/Skeletal_system |
Most of these cells develop into separate bone, cartilage, and joint cells, and they are then articulated with one another. Specialized skeletal tissues are unique to vertebrates. Cartilage grows more quickly than bone, causing it to be more prominent earlier in an animal's life before it is overtaken by bone. | https://en.wikipedia.org/wiki/Skeletal_system |
Cartilage is also used in vertebrates to resist stress at points of articulation in the skeleton. Cartilage in vertebrates is usually encased in perichondrium tissue. Ligaments are elastic tissues that connect bones to other bones, and tendons are elastic tissues that connect muscles to bones. | https://en.wikipedia.org/wiki/Skeletal_system |
In most vertebrates, the olfactory bulb is the most rostral (forward) part of the brain, as seen in rats. In humans, however, the olfactory bulb is on the inferior (bottom) side of the brain. The olfactory bulb is supported and protected by the cribriform plate of the ethmoid bone, which in mammals separates it from the olfactory epithelium, and which is perforated by olfactory nerve axons. The bulb is divided into two distinct structures: the main olfactory bulb and the accessory olfactory bulb. | https://en.wikipedia.org/wiki/Olfactory_lobes |
In most vertebrates, there are three types of enzymes that can deiodinate thyroid hormones: | https://en.wikipedia.org/wiki/Iodothyronine_deiodinase |
In most volcanoes, the crater is situated at the top of a mountain formed from the erupted volcanic deposits such as lava flows and tephra. Volcanoes that terminate in such a summit crater are usually of a conical form. Other volcanic craters may be found on the flanks of volcanoes, and these are commonly referred to as flank craters. Some volcanic craters may fill either fully or partially with rain and/or melted snow, forming a crater lake.A crater may be breached during an eruption, either by explosions or by lava, or through later erosion. | https://en.wikipedia.org/wiki/Volcanic_crater |
Breached craters have a much lower rim on one side. Some volcanoes, such as maars, consist of a crater alone, with scarcely any mountain at all. These volcanic explosion craters are formed when magma rises through water-saturated rocks, which causes a phreatic eruption. Volcanic craters from phreatic eruptions often occur on plains away from other obvious volcanoes. Not all volcanoes form craters. | https://en.wikipedia.org/wiki/Volcanic_crater |
In most wars some territory is placed under the authority of the hostile army. Most occupations end with the cessation of hostilities. In some cases the occupied territory is returned and in others the land remains under the control of the occupying power but usually not as militarily occupied territory. | https://en.wikipedia.org/wiki/Military_occupation |
Sometimes the status of presences is disputed by a party to the situation. The largest extending territories under military occupation came into existence as the outcome of World War I and World War II: Occupied Enemy Territory Administration (OETA), encompassing much of the Middle East during 1917–1920 – separated to French (OETA North) and British (OETA South) domains; Allied-occupied Germany (1945–49) in the aftermath of World War IIOccupation is usually a temporary phase, preceding either the handing back of the territory, or its annexation. A significant number of post-1945 occupations have lasted more than two decades such as the occupations of Namibia by South Africa and of East Timor by Indonesia as well as the ongoing occupations of Northern Cyprus by Turkey and of Western Sahara by Morocco. | https://en.wikipedia.org/wiki/Military_occupation |
One of the world's longest ongoing occupation is Israel's occupation of the West Bank, including East Jerusalem and the Gaza Strip (1967–present). Other prolonging belligerent occupations that have been alleged include the occupation by the United Kingdom of the Falkland Islands/Malvinas (1833–present) which Argentina claims this as sovereign territory, of Tibet by PR China (1950), and of the Hawaii by the United States (1893). The War Report makes no determination as to whether belligerent occupation is occurring in these cases.The cases of occupation, which took place in the second half of the 20th century are: Soviet occupation of Eastern European countriesOccupation of the Baltic states Conversion of Eastern European states into the Soviet satellites as part of the Eastern Bloc Soviet invasion of East Germany in 1953 Soviet invasion of Hungary in 1956 Soviet invasion of Czechoslovakia in 1968 Soviet invasion of Afghanistan in 1979 and the subsequent occupation until 1989 Egyptian occupation of Gaza, 1949/59–1967 Indian occupation of Goa, followed by its annexation (1961) Indonesian occupation of the West New Guinea, followed by its annexation (1963) Israeli occupation of the Western Golan Heights (1967–81), followed by its annexation (1981) Turkish occupation of Northern Cyprus (1974–present) Somali occupation of Ogaden in Ethiopia (1977–1978) Indonesian occupation of East Timor, followed by the annexation (1975–1999) Moroccan occupation of Western Sahara, followed most areas by its annexation (1975) Armenian-occupied territories surrounding Nagorno-Karabakh between the First Nagorno-Karabakh War and the 2020 war (1994–2020)The most recent cases of occupation, which took place in the 21st century are the: Gash-Barka Region taken over in 2000 during the Eritrean–Ethiopian War Iraq occupied by the United States during the Iraq War of 2003–2011 (See: Coalition Provisional Authority) Parts of Somalia occupied during the Somalia War (2006–2009) The Russian occupation of Georgia since 1992/2008 (See: Gori and Poti occupied by Russia during the Russo-Georgian War) Occupation of parts of Donbass region and Crimea in Ukraine by Russia since 2014, followed by its Crimea annexation in 2014 (See: Russian military intervention in Ukraine, War in Donbas, 2022 Russian invasion of Ukraine) Turkish occupation of northern Syria in support of the Syrian opposition since 2016 United Arab Emirates takeover of Socotra in 2018 during the Yemeni Civil War | https://en.wikipedia.org/wiki/Military_occupation |
In most ways, HEVC is an extension of the concepts in H.264/MPEG-4 AVC. Both work by comparing different parts of a frame of video to find areas that are redundant, both within a single frame and between consecutive frames. These redundant areas are then replaced with a short description instead of the original pixels. The primary changes for HEVC include the expansion of the pattern comparison and difference-coding areas from 16×16 pixel to sizes up to 64×64, improved variable-block-size segmentation, improved "intra" prediction within the same picture, improved motion vector prediction and motion region merging, improved motion compensation filtering, and an additional filtering step called sample-adaptive offset filtering. | https://en.wikipedia.org/wiki/High-Efficiency_Video_Coding |
Effective use of these improvements requires much more signal processing capability for compressing the video, but has less impact on the amount of computation needed for decompression. HEVC was standardized by the Joint Collaborative Team on Video Coding (JCT-VC), a collaboration between the ISO/IEC MPEG and ITU-T Study Group 16 VCEG. The ISO/IEC group refers to it as MPEG-H Part 2 and the ITU-T as H.265. | https://en.wikipedia.org/wiki/High-Efficiency_Video_Coding |
The first version of the HEVC standard was ratified in January 2013 and published in June 2013. The second version, with multiview extensions (MV-HEVC), range extensions (RExt), and scalability extensions (SHVC), was completed and approved in 2014 and published in early 2015. Extensions for 3D video (3D-HEVC) were completed in early 2015, and extensions for screen content coding (SCC) were completed in early 2016 and published in early 2017, covering video containing rendered graphics, text, or animation as well as (or instead of) camera-captured video scenes. | https://en.wikipedia.org/wiki/High-Efficiency_Video_Coding |
In October 2017, the standard was recognized by a Primetime Emmy Engineering Award as having had a material effect on the technology of television.HEVC contains technologies covered by patents owned by the organizations that participated in the JCT-VC. Implementing a device or software application that uses HEVC may require a license from HEVC patent holders. The ISO/IEC and ITU require companies that belong to their organizations to offer their patents on reasonable and non-discriminatory licensing (RAND) terms. | https://en.wikipedia.org/wiki/High-Efficiency_Video_Coding |
Patent licenses can be obtained directly from each patent holder, or through patent licensing bodies, such as MPEG LA, Access Advance, and Velos Media. The combined licensing fees currently offered by all of the patent licensing bodies are higher than for AVC. The licensing fees are one of the main reasons HEVC adoption has been low on the web and is why some of the largest tech companies (Amazon, AMD, Apple, ARM, Cisco, Google, Intel, Microsoft, Mozilla, Netflix, Nvidia, and more) have joined the Alliance for Open Media, which finalized royalty-free alternative video coding format AV1 on March 28, 2018. | https://en.wikipedia.org/wiki/High-Efficiency_Video_Coding |
In most ways, the VB.NET solution is similar to the C# solution above. However VB.NET has a unique advantage in that it allows members to be passed in to the extension by reference (C# only allows by value). Allowing for the following; Because Visual Basic allows the source object to be passed in by reference it is possible to make changes to the source object directly, without need to create another variable. It is also more intuitive as it works in a consistent fashion to existing methods of classes. | https://en.wikipedia.org/wiki/Extension_method |
In most wealthy industrialized countries, large amounts of immigration from other regions has been ongoing for many decades. This has introduced non-Western music to Western audiences not only as "exotic" imports, but also as local music played by fellow citizens. But the process is ongoing and continues to produce new forms. In the 2010s several musicians from immigrant communities in the West rose to global popularity, such as Haitian-American Wyclef Jean, Somali-Canadian K'naan, Tamil-Briton M.I.A., often blending the music of their heritage with hip-hop or pop. | https://en.wikipedia.org/wiki/World_music |
Cuban-born singer-songwriter Addys Mercedes started her international career from Germany mixing traditional elements of Son with pop.Once, an established Western artist might collaborate with an established African artist to produce an album or two. Now, new bands and new genres are built from the ground up by young performers. | https://en.wikipedia.org/wiki/World_music |
For example, the Punjabi-Irish fusion band Delhi 2 Dublin is from neither India nor Ireland, but Vancouver, British Columbia, Canada. Country for Syria, an Istanbul based music collective, blends American country music with the music of Syrian refugees and local Turkish music. Musicians and composers also work collectively to create original compositions for various combinations of western and non western instruments. | https://en.wikipedia.org/wiki/World_music |
The introduction of non-western music into western culture created a fusion that influenced both parties. (Feld 31) With the quick demand for new music came the technicalities of ownership. As Feld states in page 31: "This complex traffic in sounds money and media is rooted in the nature of revitalization through appropriation." | https://en.wikipedia.org/wiki/World_music |
There are collaborations between African and American popular music artists that raise questions on who is benefiting from said collaborations. (Feld 31) Feld mentions the example of "That was your mother". Alton Rubin and his band the Twisters collaborated with Paul Simon on the song that possessed a zydeco feel, signature of Dopsie's band. | https://en.wikipedia.org/wiki/World_music |
Even though Paul Simon wrote and sang the lyrics with them, the whole copyright is attributed to Paul and not to the band as well. (Feld 34) Because of crossovers like this one, where there was a disproportional gain when covering non-western music. Feld states that "...international music scene, where worldwide media contact, amalgamation of the music industry towards world record sales domination by three enormous companies, and extensive copyright controls by a few Western countries are having a riveting effect on the commodification of musical skill and styles, and on the power of musical ownership." | https://en.wikipedia.org/wiki/World_music |
(Feld 32) Immigration also heavily influences world music, providing a variety of options for the wider public. In the 1970s Punjabi music was greatly popular in the UK because of its growing Punjabi diaspora. (Schreffler 347) Bhangra music was also greatly covered by its diaspora in cities like New York and Chicago. | https://en.wikipedia.org/wiki/World_music |
(Schreffler 351) For a more mainstream integration, the Punjabi music scene integrated collaborations with rappers and started gaining more recognition. One of these successful attempts was a remix of the song "Mundiān ton Bach ke" called "Beware of the Boys" by Panjabi MC featuring Jay Z. (Schreffler 354) Collaborations between outsider artists provided an integration of their music, even with foreign instrumentation, into the popular music scene. | https://en.wikipedia.org/wiki/World_music |
Immigration, being a great part of music exportation, plays a big role in cultural identity. Immigrant communities use music to feel as if they are home and future generations it plays the role of educating or giving insight into what their culture is about. In Punjabi culture, music became the carrier of culture around the world. (Schreffler 355) | https://en.wikipedia.org/wiki/World_music |
In most well-studied polyomaviruses, STag improves the efficiency of viral proliferation but is not essential. SV40 and murine polyomavirus STags appear to have a role in promoting host cell expression of genes under the control of certain types of promoters. This function is mediated by the J domain, presumably indirectly as STag has no DNA-binding ability of its own. Both STag and LTag interact through their J domains with Hsc70 to increase its ATPase activity. | https://en.wikipedia.org/wiki/Small_tumor_antigen |
In most western democracies, the desire to eliminate or reduce economic inequality is generally associated with the political left. One practical argument in favor of reduction is the idea that economic inequality reduces social cohesion and increases social unrest, thereby weakening the society. There is evidence that this is true (see inequity aversion) and it is intuitive, at least for small face-to-face groups of people. Alberto Alesina, Rafael Di Tella, and Robert MacCulloch find that inequality negatively affects happiness in Europe but not in the United States.It has also been argued that economic inequality invariably translates to political inequality, which further aggravates the problem. Even in cases where an increase in economic inequality makes nobody economically poorer, an increased inequality of resources is disadvantageous, as increased economic inequality can lead to a power shift due to an increased inequality in the ability to participate in democratic processes. | https://en.wikipedia.org/wiki/Economic_inequality |
In most wireless ad hoc networks, the nodes compete for access to shared wireless medium, often resulting in collisions (interference). Collisions can be handled using centralized scheduling or distributed contention access protocols. Using cooperative wireless communications improves immunity to interference by having the destination node combine self-interference and other-node interference to improve decoding of the desired signals. | https://en.wikipedia.org/wiki/Ad_hoc_mode |
In most women, sexual desire is unchanged or increased with combined birth control pills. This is despite an increase in sex hormone-binding globulin (SHBG) levels and a decrease in total and free testosterone levels. However, findings are conflicting, and more research is needed. | https://en.wikipedia.org/wiki/Progestogen_(medication) |
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