Propeller

A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid (such as air or water) is accelerated behind the blade. Propeller dynamics, like those of aircraft wings, can be modelled by either or both Bernoulli's principle and Newton's third law. A marine propeller of this type is sometimes colloquially known as a screw propeller or screw, however there is a different class of propellers known as cycloidal propellers - they are characterized by the higher propulsive efficiency averaging 0.72 compared to the screw propellers average of 0.6 and the ability to throw thrust in any direction at any time. Their disadvantages are higher mechanical complexity and higher cost.

History

Early developments

The principle employed in using a screw propeller is used in sculling. It is part of the skill of propelling a Venetian gondola but was used in a less refined way in other parts of Europe and probably elsewhere. For example, propelling a canoe with a single paddle using a "pitch stroke" or side slipping a canoe with a "scull" involves a similar technique. In China, sculling, called "lu", was also used by the 3rd century AD.

Propeller (Peter Stuart album)

Propeller is a 2002 studio album from the American singer-songwriter Peter Stuart. The album marked Stuart's solo debut. Stuart had previously formed the rock band Dog's Eye View in 1994. Before their hiatus, Stuart had been Dog's Eye View's lead vocalist and songwriter.

The album's lead single was "With My Heart in Your Hands".

Background

Dog's Eye View founder and vocalist Peter Stuart had left the band to pursue solo projects following their 1997 release, Daisy. Stuart, who had been a solo performer prior to forming Dog's Eye View, has stated that the idea of his making a solo album originally came from the group's record label, Columbia Records:

His first solo album was originally slated to be called Songs About You. Stuart began recording the album for Columbia, which had released the first two Dog's Eye View albums, Happy Nowhere and Daisy. Early production and recording were completed in Los Angeles. However, Stuart soon became disenchanted with Columbia executives, citing a lack of support for the album and other creative differences. He voluntarily severed ties with Columbia, and left the label with the rights to his forthcoming solo album.

Propeller (band)

Propeller is an Estonian punk band formed in 1978.

Line-up (other bands where played)

External links

.download

The domain name download is a generic top-level domain (gTLD) in the Domain Name System of the Internet. It was admitted in the expansion of the top-level domain initiative of ICANN. It is intended to be used by companies or individuals offering downloadable content globally.

The domain launched in 2013-2014. Domain name registrations will be available from ICANN accredited registrars.

Second-level subdomains, e.g. example.download, may be registered. It will also be possible to register an e-mail address of the form [email protected].

See also

References

External links

Download

In computer networks, to download is to receive data from a remote system, typically a server such as a web server, an FTP server, an email server, or other similar systems. This contrasts with uploading, where data is sent to a remote server..

A download is a file offered for downloading or that has been downloaded, or the process of receiving such a file.

Definition

Downloading generally transfers the whole data object for local storage and later use, as contrasted with streaming, where the data is used nearly immediately, while the transmission is still in progress, and which may not be stored long-term.

Increasingly, websites that offer streaming media or media displayed in-browser, such as YouTube, and which place restrictions on the ability of users to save these materials to their computers after they have been received, forbid downloading in the sense of "receive and save" rather than simply "receive". Downloading is not the same as "transferring" (i.e., sending/receiving data between two storage devices would be a transferral of data, but receiving data from the Internet would be considered a download).

Music download

A music download is the digital transfer of music via the Internet into a device capable of decoding and playing it, such as a home computer, MP3 player or Smart Phone. This term encompasses both legal downloads and downloads of copyright material without permission or legal payment. According to a Nielsen report, downloadable music accounted for 55.9% of all music sales in the US in 2012. As of January 2011, Apple's iTunes Store alone made $1.1 billion of revenue in the first quarter of its fiscal year.

Online music stores

Popular online music stores that sell downloadable singles and albums include the iTunes Store, Amazon MP3, fairsharemusic, eMusic, Google Play, CD Universe, Nokia Music Store, TuneTribe, Xbox Music and MyMusic.com.ng. Paid downloads are sometimes encoded with Digital Rights Management that restricts copying the music or playing purchased songs on certain digital audio players. They are almost always compressed using a lossy codec (usually MPEG-1 Layer 3, Windows Media, or AAC), which reduces file size and bandwidth requirements. These music resources have been created as a response to expanding technology and needs of customers that wanted easy, quick access to music. Their business models respond to the "download revolution" by making legal services attractive for users.