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In signal processing, the energy Failed to parse (Missing texvc executable; please see math/README to configure.): E_s
of a continuous-time signal x(t) is defined as
- Failed to parse (Missing texvc executable; please see math/README to configure.): E_{s} \ \ = \ \ \langle x(t), x(t)\rangle \ \ = \int_{-\infty}^{\infty}{|x(t)|^2}dt
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:
- Failed to parse (Missing texvc executable; please see math/README to configure.): E = {E_s \over Z} = { 1 \over Z } \int_{-\infty}^{\infty}{|x(t)|^2}dt
- where Z represents the magnitude, in appropriate units of measure, of the load driven by the signal.
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 Failed to parse (Missing texvc executable; please see math/README to configure.): E_s
would appear as volt2-seconds, which is not dimensionally correct for energy in the sense of the physical sciences. After dividing Failed to parse (Missing texvc executable; please see math/README to configure.): E_s 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 [link]
Similarly, the spectral energy density of signal x(t) is
- Failed to parse (Missing texvc executable; please see math/README to configure.): \ E_s(f) = |X(f)|^2
where X(f) is the Fourier transform of x(t).
For example, if x(t) represents the magnitude of the electric field component (in volts per meter) of an optical signal propagating through free space, then the dimensions of X(f) would become volt-seconds per meter and Failed to parse (Missing texvc executable; please see math/README to configure.): E_s(f)
would represent the signal's spectral energy density (in volts2-second2 per meter2) as a function of frequency f (in hertz). Again, these units of measure are not dimensionally correct in the true sense of energy density as defined in physics. Dividing Failed to parse (Missing texvc executable; please see math/README to configure.): E_s(f) by Zo, the characteristic impedance of free space (in ohms), the dimensions become joule-seconds per meter2 or, equivalently, joules per meter2 per hertz, which is dimensionally correct in SI units for spectral energy density.
Parseval's Theorem [link]
As a consequence of Parseval's theorem, one can prove that the signal energy is always equal to the summation across all frequency components of the signal's spectral energy density.
See also [link]
https://wn.com/Energy_(signal_processing)
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
Sham
Sham may refer to:
Arabic use
- Bilad al-Sham the Caliphate province of the same region
- ash-Shām, or Sham (الشام), another name for Damascus, one of the largest cities in the region
- Jund al-Sham, militant group based in Afghanistan, meaning "Army of Syria"
English use
Sham (film)
Sham is a 1921 American silent romantic drama directed by Thomas N. Heffron and starring Ethel Clayton and Theodore Roberts. The film is based on the 1905 play of the same name written by Elmer Harris and Geraldine Bonner, and was adapted for the screen by Douglas Z. Doty.
Plot
Based upon a description in a film publication, Katherine Van Riper (Clayton) is an extravagant young society girl who is very much in debt, and her wealthy aunts and uncle refuse to give her any money. Katherine is desperate enough that she is considering marrying the wealthy Montee Buck (Hiers), although she is in love with the westerner Tom Jaffrey (Fillmore), who says he is poor. Finally, Katherine decides to sell the famous Van Riper pearls, pay off her debts, and marry Tom. However, upon examination the jewelry turns out to be paste, with her father having sold the genuine pearls several years earlier before his death. Montee is assured by the aunts that Katherine will marry him and tells this to Tom. Tom is about to leave town when Uncle James (Ricketts) steps in and pays off Katherine's debts, leaving the niece free to marry Tom.
Bilad al-Sham
Bilad al-Sham (Arabic: بلاد الشام, "the country of Syria") was a Rashidun, Umayyad and later Abbasid Caliphate province in the region of Syria. It incorporated former Byzantine territories of the Diocese of the East, organized soon after the Muslim conquest of Syria in the mid-7th century, which was completed at the decisive Battle of Yarmouk.
History
At the time of the Arab conquest under the Rashidun and the subsequent eviction of the region's Byzantine rulers, the Bilad al-Sham (Levant) region had been inhabited mainly by local Aramaic-speaking Monophysite Christian peasants (like the Mardaites) who constituted the bulk of the native population, by Ghassanid and Nabatean Arabs, as well as by non-Monophysite Greek Orthodox Christian minorities called Melchites or Rûm (which in that particular context means "Eastern Roman" or "Byzantine") and by non-Christian minorities of Jews, Samaritans and Ismaelite Itureans. The population of the region did not become predominantly Muslim and Arab in identity until nearly a millennium after the conquest.
Podcasts:
-
by Snapcase
Energy Dome
by: Snapcasecan you... feel your heartbeat, are you living? your mind is unsung because youre not driven you need to rise up and personalize your existence you need to wake up and activate the dreams of your soul idle, revolt, hero, your hero is yourself theyll break you in, theyll break you down and leave you down with nothing you lose yourself and learn from them whatever they wish to teach you you need to rise up and revolutionize your thinking you need to wake up and activate the dreams of your soul idle, revolt, hero, your hero is yourself you know your dead and its you your decieving you need to find a way, to yourself, find a way, to make yourself live, to make yourself live you need to rise up and revolutionize your thinking you need to wake up and activate the dreams of your soul you need to find a way to make your self live