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Electric current

An electric current is the rate of flow of electric charge past a point or region. An electric current is said to exist through a region. In electric circuits this charge is carried by electrons moving through a wire, it can be carried by ions in an electrolyte, or by both ions and electrons such as in an ionized gas. The SI unit of electric current is the ampere, the flow of electric charge across a surface at the rate of one coulomb per second; the ampere is an SI base unit. Electric currents cause Joule heating, they create magnetic fields, which are used in motors and generators. The moving charged. In metals, one or more electrons from each atom are loosely bound to the atom, can move about within the metal; these conduction electrons are the charge carriers in metal conductors. The conventional symbol for current is I, which originates from the French phrase intensité du courant. Current intensity is referred to as current; the I symbol was used by André-Marie Ampère, after whom the unit of electric current is named, in formulating Ampère's force law.

The notation travelled from France to Great Britain, where it became standard, although at least one journal did not change from using C to I until 1896. In a conductive material, the moving charged particles that constitute the electric current are called charge carriers. In metals, which make up the wires and other conductors in most electrical circuits, the positively charged atomic nuclei of the atoms are held in a fixed position, the negatively charged electrons are the charge carriers, free to move about in the metal. In other materials, notably the semiconductors, the charge carriers can be positive or negative, depending on the dopant used. Positive and negative charge carriers may be present at the same time, as happens in an electrolyte in an electrochemical cell. A flow of positive charges gives the same electric current, has the same effect in a circuit, as an equal flow of negative charges in the opposite direction. Since current can be the flow of either positive or negative charges, or both, a convention is needed for the direction of current, independent of the type of charge carriers.

The direction of conventional current is arbitrarily defined as the same direction as positive charges flow. Since electrons, the charge carriers in metal wires and most other parts of electric circuits, have a negative charge, as a consequence, they flow in the opposite direction of conventional current flow in an electrical circuit. Since the current in a wire or component can flow in either direction, when a variable I is defined to represent that current, the direction representing positive current must be specified by an arrow on the circuit schematic diagram; this is called the reference direction of current I. If the current flows in the opposite direction, the variable I has a negative value; when analyzing electrical circuits, the actual direction of current through a specific circuit element is unknown. The reference directions of currents are assigned arbitrarily; when the circuit is solved, a negative value for the variable means that the actual direction of current through that circuit element is opposite that of the chosen reference direction.

In electronic circuits, the reference current directions are chosen so that all currents are toward ground. This corresponds to the actual current direction, because in many circuits the power supply voltage is positive with respect to ground. Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance, one arrives at the usual mathematical equation that describes this relationship: I = V R where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, R is the resistance of the conductor in units of ohms. More Ohm's law states that the R in this relation is constant, independent of the current. In alternating current systems, the movement of electric charge periodically reverses direction. AC is the form of electric power most delivered to businesses and residences.

The usual waveform of an AC power circuit is a sine wave. Certain applications use different waveforms, such as square waves. Audio and radio signals carried on electrical wires are examples of alternating current. An important goal in these applications is recovery of information encoded onto the AC signal. In contrast, direct current is the unidirectional flow of electric charge, or a system in which the movement of electric charge is in one direction only. Direct current is produced by sources such as batteries, solar cells, commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can flow through semiconductors, insulators, or through a vacuum as in electron or ion beams. An old name for direct current was galvanic current. Natural observable examples of electrical current include lightning, static electric discharge, the solar wind, the source of the polar auroras. Man-made occurrences of electric current include the flow of conduction electrons in metal wires such as the overhead power lines that deliver electrical energy across long distances and the smaller wi

List of Space Launch System launches

As of 2019, four flights of the Space Launch System – a Shuttle-derived, super heavy-lift expendable launch vehicle – are planned for the 2020s. The current launch manifest includes three flights in support of the Artemis program, a human spaceflight project aimed at establishing a permanent human presence on the Moon, the launch of the Europa Clipper to Jupiter; the flights will launch from the vehicle's dedicated pad at Kennedy Space Center's Launch Complex 39B, will use either its Block 1 configuration with a modified Delta Cryogenic Second Stage known as the Interim Cryogenic Propulsion Stage, or its Block 1B configuration with the Exploration Upper Stage. In early 2019, then-Associate Administrator for Human Exploration William H. Gerstenmaier drafted a proposal for five more launches of SLS Block 1B launch vehicles between 2024 and 2028 in support of the Artemis program; these include four crewed launches of the Orion spacecraft. In 2012, Skylab II was proposed by an engineer working with NASA's Marshall Space Flight Center.

It would use the EUS hydrogen tank to build a 21st-century version of Skylab. The SLS has been proposed as the launch vehicle for the future Large UV Optical Infrared Surveyor space telescope, which will have a main segmented mirror between 8 and 16 meters in diameter, making it 300 times more powerful than Hubble Space Telescope, it would be deployed at the Earth-Sun L2 point in 2035. Proposals by Bigelow Aerospace, Lockheed Martin, Orbital ATK, Sierra Nevada Corporation, Space Systems Loral, NanoRacks to build the Deep Space Habitat – a spacecraft with a large enough living space for humans to travel to destinations such as Mars, near Earth asteroids, or cislunar space – all envisioned a launch aboard an SLS vehicle; the proposed Europa Lander, a part of the Europa Clipper mission, is now proposed to be launched aboard an SLS in the mid-2020s. The joint NASA-ESA Titan Saturn System Mission proposal envisioned the SLS as an option for launch; the SLS has been proposed by Boeing as a launch vehicle for a Uranus probe concept developed by NASA.

The rocket would "deliver a small payload into orbit around Uranus and a shallow probe into the planet's atmosphere." The mission would study the Uranian atmosphere and thermal characteristics, gravitational harmonics, as well as do flybys of Uranian moons. In addition, a 2017 study suggested that a single SLS Block 1B launch vehicle could launch two spacecraft, one to each ice giant, with launch dates suggested from 2024 to 2037 followed by a four-year transit time. List of Atlas launches List of Falcon 9 and Falcon Heavy launches List of Thor and Delta launches Notes Citations Space Launch System at NASA Space Launch System at Boeing

Plithocyon

Plithocyon is an extinct genus of hemicyonine bear of the Miocene epoch, endemic to North America and Europe. It lived from ~15.97—11.61 Ma, existing for 4 million years. Sites and age of some specimens: Hemicyon Quarry, Barstow Formation, San Bernardino County, California ~13.7—11.6 Ma. Ruby River Basin No.5, Madison County, Montana ~23—5.3 Ma. Pasalar site, Turkey ~16—13.7 Ma. Pontigne site, France ~11.6—7.2 Ma. Plithocyon antunesi Ginsburg & Morales, 1998 Plithocyon armagnacensis Ginsburg, 1955 Plithocyon barstowensis Frick, 1926 Plithocyon bruneti Ginsburg, 1980 Plithocyon conquense Ginsberg Plithocyon ursinus Cope, 1875 Ginsburg, L. & Morales, J. 1998. Les Hemicyoninae et les formes apparentées du Miocène moyen d'Europe occidentale. Ann. Paléontol. 84: 71-123

Rodeo (Travis Scott album)

Rodeo is the debut studio album by American rapper Travis Scott. It was distributed by Epic Records; the album features guest appearances from Quavo, Future, 2 Chainz, Juicy J, Kacy Hill, The Weeknd, Swae Lee, Chief Keef, Kanye West, Justin Bieber, Young Thug, Toro y Moi and Schoolboy Q, while the production was provided by Scott himself, alongside several high-profile record producers such as Allen Ritter, Mike Dean, Metro Boomin, Frank Dukes, Sonny Digital and WondaGurl, among others. Rodeo was supported by two singles: "3500" and "Antidote"; the latter became his highest-charting single in the US Billboard Hot 100 at the time, peaking at number 16. The album received positive reviews from critics and debuted at number three on the US Billboard 200, it debuted at number one on the US Rap Albums chart. In May 2017, the album was certified platinum by the Recording Industry Association of America. Travis Scott announced the release date for Rodeo through social media on July 17, 2015. In the CR Fashion Book, Scott stated his life was like a rodeo and he feels like he is trying to stay on a bucking animal: It's like a Beyoncé concert.

The carnival, the livestock, the show are all parts of the event. I feel; the carnival is like my imagination—it's the drive behind my vision. Though I don't feel like I'm at a point where my shit is at an all time high, we're working to get there. We are working to stand on that level; the livestock show is the road to get to. At this point, I'm riding a bull for just eight seconds and it's hard as fuck, but we made it. On January 26, 2015, to support the album, Scott announced he would embark on The Rodeo Tour with Young Thug and Metro Boomin. On January 27, the following day, Scott released two new songs. However, neither of them ended up being on the final version of the album. On June 12, 2015, a track titled "Drunk" featuring Young Thug, leaked online. However, it was still included on the album as "Maria I'm Drunk" with an additional verse by Justin Bieber. On June 8, 2015, Scott released the album's lead single, "3500", which features guest appearances from American rappers Future and 2 Chainz.

It peaked at number 82 on the US Billboard Hot 100. On July 29, 2015, Scott released the album's second single, "Antidote"; the song peaked at number 16 on the US Billboard Hot 100. On April 14, 2017, the song was certified triple platinum by the Recording Industry Association of America. Rodeo received positive reviews from critics. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream publications, the album received an average score of 64, based on 15 reviews. Roger Krastz of XXL stated, "Overall, Rodeo has plenty of bangers and noteworthy collaborations that help bring out a fantastic trap sound that could bleed into the mainstream of hip-hop in no time." Jason Bisnoff of HipHopDX stated, "Rodeo's back end after "Antidote" begin to mesh together and gets repetitive.... Nonetheless, the originality of Scott's sound within this new movement provides for a strong rookie effort leaving the listener excited for a career, just getting started." Trazier Tharpe of Complex stated, "Travis Scott made an enjoyable album for his fans peppered with undeniable bangers for his detractors."

David Jeffries of AllMusic stated, "With Rodeo, Travis Scott becomes a designer drug." Steve "Flash" Juon of RapReviews stated, "Somewhere beneath all the hype and production he does shine through." Martin Caballero of The Boston Globe stated, "His versatility, combined with a high-profile guest list, conspires against him. Kevin Ritchie of Now stated, "Scott goes for spacey sounds, stoner vibes and vocal filters, but despite the eclecticism, he's too elusive and bland for Rodeo to amount to a stylistic--let alone a subversive--statement." Sheldon Pearce from Pitchfork stated, "He is most effective when he harshly distorts his vocals to create texture, in the company of others he can serve as a welcome change of pace." David Turner from Rolling Stone stated, "Left on his own, Scott can grow tiresome. "I Can Tell" sounds monochromatic without another voice to push this astute curator. Some rock stars are better leading bands than going solo." Matthew Ramirez of Spin stated, "This is a cold, calculated record lacking in personality, though it tries to deliver something that Scott is incapable of."

Rodeo debuted at number three on the US Billboard 200, moving 85,000 album-equivalent units, of which 70,000 are pure album sales. It debuted at number one on the US Rap Albums chart; as of November 2015, Rodeo has sold 110,000 copies in the United States. In May 2017, the album was certified platinum by the Recording Industry Association of America for combined sales and album-equivalent units of over 1,000,000 units. Credits were adapted from Tidal. Track notes ^ signifies an additional producer ^ signifies a co-producer Some songs have different mixes on the physical copies of the album as opposed to the digital copies "Pornography", "Wasted" and "Apple Pie" feature narration by T. I. "Oh My Dis Side" features additional vocals by River Tiber "90210" features additional vocals by Chantel Jeffries on the physical copies of the album "Ok Alright" features additional vocals by SZA and Kacy Hill "Never Catch Me" features

Partabpura

Partabpura is a village in Jalandhar District of Punjab. Partabpura is on the Phillaur-Nurmahal road, close to Bilga village. Partabpura is well linked by road with Nurmahal, Phillaur and other neighboring villages and towns, it has historical gurudwaras and mosques. Village is divided in 4 portions. Partabpura Railway Station serves this area. Phillaur is nearest railway junction; the nearest airport is at Ludhiana. Partabura is the biggest village in the immediate area. Partabpura is located at 31.04°N 75.71°E / 31.04. It has an average elevation of 243 metres. Govt. Primary School Guru Nanak Public School SBS Evershine Convent School Govt. Sen. Sec. School I. T. I. College Partabpura's PIN code and STD code are 01826 respectively. Media related to Partabpura at Wikimedia Commons Partabpura on Facebook

G.722

G.722 is an ITU-T standard 7 kHz wideband audio codec operating at 48, 56 and 64 kbit/s. It was approved by ITU-T in November 1988. Technology of the codec is based on sub-band ADPCM; the corresponding narrow-band codec based on the same technology is G.726. G.722 provides improved speech quality due to a wider speech bandwidth of 50–7000 Hz compared to narrowband speech coders like G.711 which in general are optimized for POTS wireline quality of 300–3400 Hz. G.722 sample audio data at a rate of 16 kHz, double that of traditional telephony interfaces, which results in superior audio quality and clarity. Other ITU-T 7 kHz wideband codecs include G.722.1 and G.722.2. These codecs are not variants of G.722 and they use different patented compression technologies. G. 722.1 offers lower bit-rate compressions. It uses a modified discrete cosine transform audio coding data compression algorithm. A more recent G.722.2 known as AMR-WB is based on ACELP and offers lower bit-rate compressions, as well as the ability to adapt to varying compressions as the network topography mutates.

In the latter case, bandwidth is automatically conserved. When congestion returns to a normal level, a lower-compression, higher-quality bitrate is restored. G.722 is an ITU standard codec that provides 7 kHz wideband audio at data rates from 48, 56 and 64 kbit/s. This is useful for voice over IP applications, such as on a local area network where network bandwidth is available, offers a significant improvement in speech quality over older narrowband codecs such as G.711, without an excessive increase in implementation complexity. Environments where bandwidth is more constrained may prefer one of the more bitrate-efficient codecs, such as G.722.1 or G.722.2. G.722 has been used by radio broadcasters for sending commentary-grade audio over a single 56 or 64 kbit/s ISDN B-channel. G.722 works by having the inbound voice signal pass through a digital filter that splits the audio signal into 0 Hz-to-4 kHz and 4 kHz-to-8 kHz audio bands. These sub-bands are encoded using sub-band ADPCM. Most of the human voice energy is concentrated in the lower half of the audio band, so 48 kbit/s of the bandwidth is dedicated to the lower sub-band and the other 16 kbit/s is allocated to the higher sub-band.

G.722 VoIP is carried in RTP payload type 9. Note that IANA records the clock rate for type 9 G.722 as 8 kHz, RFC 3551 clarifies that this is due to a historical error and is retained in order to maintain backward compatibility. Correct implementations represent the value 8,000 where required but encode and decode audio at 16 kHz. Whilst G.722 allows for bitrates of 64, 56 and 48 kbit/s, in practice, data is encoded at 64 kbit/s, with bits from the lower sub-band being used to encode auxiliary data. The greater the lower the bit rate. G.722 patents have expired, so it is available. List of codecs Comparison of audio coding formats Wideband audio ITU-T Recommendation G.722: 7 kHz audio-coding within 64 kbit/s- technical specification