Energy (signal processing)

In signal processing, the energy of a continuous-time signal x(t) is defined as

the energy of a discrete-time signal x(t) is defined as

Relationship to energy in physics

Energy in this context is not, strictly speaking, the same as the conventional notion of energy in physics and the other sciences. The two concepts are, however, closely related, and it is possible to convert from one to the other:

For example, if x(t) represents the potential (in volts) of an electrical signal propagating across a transmission line, then Z would represent the characteristic impedance (in ohms) of the transmission line. The units of measure for the signal energy would appear as volt²·seconds, which is not dimensionally correct for energy in the sense of the physical sciences. After dividing by Z, however, the dimensions of E would become volt²·seconds per ohm, which is equivalent to joules, the SI unit for energy as defined in the physical sciences.

Spectral energy density

Seven Year Itch (Collective Soul album)

On September 18, 2001, Collective Soul released their greatest hits compilation Seven Year Itch: Greatest Hits, 1994-2001 (stylized as 7even Year Itch). The compilation includes songs recorded from 1994 to 2001 and included two new tracks; "Next Homecoming" and "Energy". Seven Year Itch received decent reviews and was relatively successful It sold 225,000 copies in the first year after its release and reached number fifty on the Billboard 200; in Canada, it reached number nine on its albums chart and went platinum. All the songs in Seven Year Itch had charted in the US on the Billboard Hot 100, Mainstream Rock Tracks, or the Modern Rock Tracks chart, except for "Energy", which debuted in this compilation.

The compilation has sold over 500,000 copies. It saw a resurgence in sales after Collective Soul began putting out albums on their own independent label, El Music Group, beginning in 2004.

Seven Year Itch was the last album Collective Soul released through Atlantic Records and their last album to feature guitarist Ross Childress, who had been with the band since its 1993/1994 debut.

Energy (Drake song)

"Energy" is the second single by Canadian rapper Drake from his fourth commercial release If You're Reading This It's Too Late.

Composition

"Energy" contains samples from Eazy-Duz-It performed by Eazy-E and Ridin Spiners performed by Three 6 Mafia. Energy was produced by Boi-1da and OB O'Brien. According to WhoSampled the song samples the score of an episode of The O.C..

Critical reception

"Energy" received acclaim from music critics with many calling it the best song of the album. Ryan Dombal of Pitchfork gave the song a positive review and named it "Best New Track", stating "The song isn't aimed to any rappers or pop stars, not Kendrick Lamar, Big Sean or Tyga, but the song lines are dangerous."

Music video

Release

The video of "Energy" was released on Apple Music and users with iTunes and registered Apple Music account can watch this video.

Synopsis

Hydro

Hydro may refer to:

Energy technologies

Utilities

Australia:

Canada:

Europe:

Other uses

Places:

Personal names:

Hydro (fuel-station chain)

Hydro was a chain of fuel stations throughout Sweden owned by Statoil. The chain had more than 500 stations, as well as some unmanned Uno-X stations. The company also operated in retailing natural gas, electricity and heating oil.

History

The Hydro chain was created in the late 1980s when Norsk Hydro bought the Mobil stations in Norway, Sweden and Denmark to transform itself to a vertically integrated petroleum company. The stations were rebranded Hydro in all three countries. In 1995 the Norwegian and Danish stations were converted to Hydro Texaco when Hydro merged its stations in the two countries with Texaco's stations. In 2007 the ownership of Hydro was transferred to StatoilHydro when Norsk Hydro's oil and gas division merged with Statoil. When StatoilHydro was renamed Statoil in November 2009, the use of the Hydro-brand was discontinued and ownership of the Hydro filling stations was transferred to St1.

References

External links

List of Marvel Comics characters: H

Haazareth Three

The Haazareth Three debuted in Fantastic Four Vol 3 #69 (2003). They operate out of the hellish realm ruled by Mephisto. They are a trio of demons with whom Doctor Doom made a pact (seen in the Unthinkable story arc). They made a deal with Doom; if he sacrifices something of irreplaceable value, they would provide him with the magical powers he would have possessed if he had chosen to devote his life to studying magic over science. Doom does, killing his childhood sweetheart, Valeria. The demons come through with the deal.

Hack

Hack is a mutant whose first appearance was in Excalibur vol. 2 #2. He was one of the few survivors after Cassandra Nova programmed her Wild Sentinels to decimate the island nation of Genosha, killing over 16 million mutants. He found other survivors and allied himself with Unus the Untouchable and his gang. He was a very valuable asset on the island since all forms of electronic communication were eradicated or made useless by the resulting electro-magnetic damage. Inside of the gang, he became close friends with Hub and the two of them began to doubt if Unus' exclusive, clique-like strategy was the best way. Hack was gifted with a finely tuned form of telepathy that allowed him to "hack" into almost any mind.