|
QR Code
A QR code (an initialism for quick response code) is a type of Barcode#Matrix (2D) barcodes, matrix barcode (or two-dimensional barcode) invented in 1994 by the Japanese company Denso#Denso Wave, Denso Wave. A barcode is a machine-readable optical label that can contain information about the item to which it is attached. In practice, QR codes often contain data for a locator, identifier, or Website visitor tracking, tracker that points to a website or application. QR codes use four standardized encoding modes (numeric, alphanumeric, byte/binary, and kanji) to store data efficiently; extensions may also be used. The quick response system became popular outside the automotive industry due to its fast readability and greater storage capacity compared to standard Universal Product Code, UPC barcodes. Applications include product tracking, item identification, time tracking, document management, and general marketing. A QR code consists of black squares arranged in a square grid on a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queensland Rail
Queensland Rail (QR) is a railway operator in Queensland, Australia. Owned by the Queensland Government, it operates local and long-distance passenger services, as well as owning and maintaining approximately 6,600 kilometres of track and related infrastructure. QR was also responsible for all Queensland freight services, and from 2002 operated interstate services under the Australian Railroad Group, Interail and QR National brands. These were all spun out into a separate entity in July 2010, and later privatised as Aurizon. History Beginnings Queensland Railways was the first operator in the world to adopt narrow gauge (in this case ) for a main line, and this remains the systemwide gauge within Queensland today. The colony of Queensland separated from New South Wales in 1859, and the new government was keen to facilitate development and immigration. Improved transport to the fertile Darling Downs region situated west of Toowoomba was seen as a priority. As adequate ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QR Decomposition
In linear algebra, a QR decomposition, also known as a QR factorization or QU factorization, is a decomposition of a matrix ''A'' into a product ''A'' = ''QR'' of an orthogonal matrix ''Q'' and an upper triangular matrix ''R''. QR decomposition is often used to solve the linear least squares problem and is the basis for a particular eigenvalue algorithm, the QR algorithm. Cases and definitions Square matrix Any real square matrix ''A'' may be decomposed as : A = QR, where ''Q'' is an orthogonal matrix (its columns are orthogonal unit vectors meaning and ''R'' is an upper triangular matrix (also called right triangular matrix). If ''A'' is invertible, then the factorization is unique if we require the diagonal elements of ''R'' to be positive. If instead ''A'' is a complex square matrix, then there is a decomposition ''A'' = ''QR'' where ''Q'' is a unitary matrix (so If ''A'' has ''n'' linearly independent columns, then the first ''n'' columns of ''Q'' for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
QR Algorithm
In numerical linear algebra, the QR algorithm or QR iteration is an eigenvalue algorithm: that is, a procedure to calculate the eigenvalues and eigenvectors of a matrix. The QR algorithm was developed in the late 1950s by John G. F. Francis and by Vera N. Kublanovskaya, working independently. The basic idea is to perform a QR decomposition, writing the matrix as a product of an orthogonal matrix and an upper triangular matrix, multiply the factors in the reverse order, and iterate. The practical QR algorithm Formally, let ''A'' be a real matrix of which we want to compute the eigenvalues, and let ''A''0:=''A''. At the ''k''-th step (starting with ''k'' = 0), we compute the QR decomposition ''A''''k''=''Q''''k''''R''''k'' where ''Q''''k'' is an orthogonal matrix (i.e., ''Q''''T'' = ''Q''−1) and ''R''''k'' is an upper triangular matrix. We then form ''A''''k''+1 = ''R''''k''''Q''''k''. Note that : A_ = R_k Q_k = Q_k^ Q_k R_k Q_k = Q_k^ A_k Q_k = Q_k^ A_k Q_k, so all the ''A''''k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nissan QR Engine
The QR family of inline-four piston engines by Nissan were introduced in 2000 and range from in displacement. These motors are aluminum, dual overhead camshaft (DOHC), four-valve designs with variable valve timing and optional direct injection. The engine shares much of its architecture with the YD diesel engine. QR20DE QR20DE The QR20DE produces at 6000 rpm and at 4000 rpm. The bore and stroke is and a compression ratio of 9.9:1. The QR20DE was replaced with the MR20DE engine in most applications in early 2005. Vehicle applications: * 2001-2007 Nissan X-Trail T30, * 2001-2007 Nissan Primera P12 * 2002–present Nissan Serena C24, * 2003-2008 Nissan Teana J31, * 2001-2005 Nissan Wingroad Y11 * 2002-2005 Nissan Avenir W11 * 2001-2004 Nissan Prairie M12 * 2007-2020 Nissan Atlas F24 QR20DD The QR20DD is similar to the QR20DE but features NEO direct injection to improve fuel economy and to reduce emissionIt produces at 6000 rpm and at 4400 rpm. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qatar Airways
Qatar Airways Company Q.C.S.C. ( ar, القطرية, ''al-Qaṭariya''), operating as Qatar Airways, is the state-owned flag carrier airline of Qatar. Headquartered in the Qatar Airways Tower in Doha, the airline operates a hub-and-spoke network, flying to over 150 international destinations across Africa, Asia, Europe, the Americas, and Oceania from its base at Hamad International Airport, using a fleet of more than 200 aircraft. Qatar Airways Group employs more than 43,000 people. The carrier has been a member of the Oneworld alliance since , the first Persian Gulf carrier to sign with one of the three major airline alliances. History Origin Qatar was a joint-owner member of Bahrain-based Gulf Air along with Oman, the UAE Emirate of Abu Dhabi, and Kingdom of Bahrain, until its May 2002 withdrawal, making it the first Gulf country to withdraw from the airline, although it remained a member of the airline for six months after the government announced its withdrawal. Founda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quiet Riot
Quiet Riot is an American heavy metal band founded in Los Angeles in 1973 by guitarist Randy Rhoads and bassist Kelly Garni. The original lineup featured Rhoads and Garni with lead vocalist Kevin DuBrow and drummer Drew Forsyth, though that version of the band was mired in turmoil that would eventually see Garni fired for making death threats towards DuBrow. Their most commercially successful lineup consisted of DuBrow alongside guitarist Carlos Cavazo, bassist Rudy Sarzo and drummer Frankie Banali, and in 1983 released their breakthrough album ''Metal Health'', which is known for being the first heavy metal album to top the ''Billboard'' album chart. The band had several hit singles which charted on the Billboard Hot 100, including " Cum On Feel the Noize", "Mama Weer All Crazee Now" (both cover songs of the glam rock band Slade), and " Metal Health (Bang Your Head)". The band is ranked at No. 100 on VH1's 100 Greatest Artists of Hard Rock. Despite several lineup cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nippon Cultural Broadcasting
is a Japanese radio station in Tokyo which broadcasts to the Kanto area. It is one of the two flagship radio stations of National Radio Network (NRN) (the other station is ) and is a member of the Fujisankei Communications Group. History The station was established in 1951 by the Society of St. Paul to promote Catholic religion on the Japanese culture. JOQR went on the air on March 31, 1952 as the Japan Cultural Broadcasting Association. Japan Cultural Broadcasting Association was formally dissolved on February 16, 1956 and the JOQR broadcast license was handed over the same day to a new succeeding company, Nippon Cultural Broadcasting Co., Ltd. In 1957, Cultural Broadcasting established Fuji Television as part of a joint venture with Nippon Broadcasting System. Cultural Broadcasting was one of the founding companies behind the creation of the Fujisankei Communications Group in 1967. To this day, Cultural Broadcasting remains associated with the Fujisankei Communications Gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quintana Roo (company)
Quintana Roo (QR) was the first company to create a triathlon-specific wetsuit over 25 years ago, and then a tri-specific bicycle two years later. The company was founded in 1987 by Dan Empfield of Ironman fame and is currently owned by the American Bicycle Group. Wetsuits The company's flagship product in 1987 was the first wetsuit made specifically for triathlon, designed by Empfield. This new wetsuit was more flexible and more buoyant, giving it swim-specific characteristics that were not found in the diving or surfing wetsuits used by triathletes at that time. In 1990, Quintana Roo discovered and pioneered the use of Yamamoto Rubber #39 in its high-end wetsuits. This new rubber was more buoyant and more flexible than any other rubber that had previously been used in any triathlon wetsuit, and it was followed the next year with Yamamoto SCS (Super-Composite Skin), an outer coating that added even more buoyancy and protected the rubber from fingernail tears. Triathlon-specif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queen's Radio
Queen's Radio (or QR) is a student radio station, broadcasting a wide variety of shows, based at Queen's University, Belfast, Northern Ireland, currently broadcasting via online stream. Its studios are located in the Students' Union building. It is the only licensed student station broadcasting in Northern Ireland, and one of several on the island. History Queen's Radio began broadcasting on 29 September 2003, initially over the Queen's University campus network and then the internet. In late 2005, the station was successful in acquiring a low-powered AM licence, allowing it to broadcast to Queen's Halls of Residence ( Elms Village) directly via Medium Wave. This service commenced on 6 February 2006. Queen's Radio is operated by the 'Queen's University of Belfast Radio Club', which was originally formed in 1953, making it two years older than the independent student newspaper The Gown. The old Radio Club was a general purpose electronics, amateur radio and computer club, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queensrÿche
Queensrÿche is an American heavy metal band. It formed in 1982 in Bellevue, Washington, out of the local band the Mob. The band has released 16 studio albums, one EP, and several DVDs, and continues to tour and record. The original lineup consisted of guitarists Michael Wilton and Chris DeGarmo, drummer Scott Rockenfield, bassist Eddie Jackson, and lead vocalist Geoff Tate. Queensrÿche has sold over 20 million albums worldwide, including over six million albums in the United States. They are considered one of the leaders of the progressive metal scene of the mid-to-late 1980s, and often referred to as one of the "Big Three" of the genre, along with Dream Theater and Fates Warning. The band received worldwide acclaim after the release of their 1988 album '' Operation: Mindcrime'', which is often considered one of the greatest heavy metal concept albums of all time. Their next album, ''Empire'' (1990), was also very successful and included the hit single "Silent Lucidity" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasireversibility
In queueing theory, a discipline within the mathematical theory of probability, quasireversibility (sometimes QR) is a property of some queues. The concept was first identified by Richard R. Muntz and further developed by Frank Kelly. Quasireversibility differs from reversibility in that a stronger condition is imposed on arrival rates and a weaker condition is applied on probability fluxes. For example, an M/M/1 queue with state-dependent arrival rates and state-dependent service times is reversible, but not quasireversible. A network of queues, such that each individual queue when considered in isolation is quasireversible, always has a product form stationary distribution. Quasireversibility had been conjectured to be a necessary condition for a product form solution in a queueing network, but this was shown not to be the case. Chao et al. exhibited a product form network where quasireversibility was not satisfied. Definition A queue with stationary distribution \pi is quasire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.gif "Click for more on -> QR Algorithm")
.jpg "Click for more on -> Quiet Riot")
