The Observer

Oh My! Productions Ltd

iucn3.1

Wild Hearts

Four-spot megrim

The classical four-vertex theorem states that the curvature function of a simple, closed, smooth plane curve has at least four local extrema (specifically, at least two local maxima and at least two local minima). The name of the theorem derives from the convention of calling an extreme point of the curvature function a vertex. This theorem has many generalizations, including a version for space curves where a vertex is defined as a point of vanishing torsion.

Joshua Sanchez

Libellula

Four (disambiguation)

Four-thousand footers (sometimes abbreviated "4ks") is a term referring to a group of forty-eight mountains in New Hampshire at least 4,000 feet (1,219 meters) above sea level. To qualify for inclusion a peak must also meet the more technical criterion of topographic prominence important in the mountaineering sport of "peak-bagging".Most often, the term refers to the White Mountains Four Thousand Footers List established (and revised from time to time) by the Appalachian Mountain Club. The AMC calls it the White Mountains List, but others call it the New Hampshire List because it does not include Old Speck Mountain (4,170 ft), located in Maine (and outside the White Mountain National Forest) but within the White Mountains.The AMC also maintains a list of New England 4000 Footers, all falling within Vermont, New Hampshire, and Maine. Other lists of 4000-footers not maintained by the AMC include the original set of 4,000-foot mountains for peak-bagging: the 46 High Peaks in the Adirondacks.The AMC has revised its 4000-footer lists as surveying became more accurate or the selection criteria were adjusted, with the White Mountains list growing from 46 peaks in the 1950s to 48 in 1982. The proper inclusion or exclusion of several peaks is still a matter of some dispute.The 48 lie in the White Mountain National Forest and within two of the northernmost counties of New Hampshire, Coos and Grafton. All peaks except those of Mount Washington, Mount Moosilauke and Cannon Mountain are on land owned by the Forest Service, and even these three are almost completely surrounded by it.

The four-toed jerboa (Allactaga tetradactyla) is a rodent of the family Dipodidae and genus Allactaga that has four digits. They are native to Egypt and Libya. Four-toed jerboas live in coastal salt marshes and dry deserts.

The four-spotted chaser (Libellula quadrimaculata), known in North America as the four-spotted skimmer, is a dragonfly of the family Libellulidae found frequently throughout Europe, Asia, and North America.The adult stage is found between April to early September in the United Kingdom, and from mid-May to mid-August in Ireland. Larvae have a two-year developmental cycle.

X-Cutioner's Song

Four-spot orb-weaver

Four0ninE

Glorious

Four-tube television camera

Four

Atelerix albiventris

Four-spotted barb

Four (SAB TV)

Deluxe edition bonus tracks

Four-year plan

The four-toed rice tenrec (Oryzorictes tetradactylus) is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, subtropical or tropical high-altitude shrubland, subtropical or tropical high-altitude grassland, and swamps.

Four-toed jerboa

The four-toed earless skink (Hemiergis peronii ), also known commonly as Péron's earless skink, the lowlands earless skink, or the four-toed mulch skink, is a viviparous earless skink endemic to southern Australia.

FourGen CASE Tools

FourTwoNine (the numbers spell out "gay" on a cellphone keypad) is an American "glossy" print publication. FourTwoNine is an up-to-the-minute men’s brand aimed at thought influencers and cultural leaders of all genders.

FourFourTwo TV Show

Four-wheel drive in Formula 1

Four-spotted footman

Four0ninE is the first EP by Canadian grindcore band Fuck the Facts. It was recorded in mid May 2001 by the band. It marks the first recordings with vocalist Brent Christoff, and the only recordings with bassist Shomir Das. It is the second release by Fuck the Facts as a band, the first being a split with Ames Sanglates. Days after the recording of this EP, Shomir left the band.

Four-striped Grass Mouse

Four-way switch

FourTwoNine (the numbers spell out "gay" on a cellphone keypad) is an American "glossy" print publication. FourTwoNine is an up-to-the-minute men’s brand aimed at thought influencers and cultural leaders of all genders. Created by some of the industry’s most prominent writers, editors, artists and photographers, each issue of FourTwoNine highlights the latest news in culture, style, sports, technology, business and politics, while casting a spotlight on the leaders and innovators who are driving contemporary culture.It was founded in 2013 by Richard Klein, founder and former publisher of Surface It is based in Los Angeles.

A FourCC (literally, four-character code) is a sequence of four bytes used to uniquely identify data formats.The concept originated in the OSType scheme used in the Macintosh system software and was adopted for the Amiga/Electronic Arts Interchange File Format and derivatives. The idea was later reused to identify compressed data types in QuickTime and DirectShow.

Four-toed tegu

Insecta

Four-toed Salamander

Four-way stop

Go Home'

THREE

Sketches from the Book of the Dead

Lariscus

Alligator Wine

Four-toed salamander

FourWays Restaurant

A four-year junior college was a type of educational institution in the United States in the 20th century that provided education from the 11th to the 14th grades, corresponding to the last two years of high school and the first two years of college. Although these are now considered secondary education and tertiary education respectively, advocates of the four-year junior college argued that all four years should be considered part of secondary education.The first proposal for four-year junior colleges was made in 1894, by George A. Merrill, Director of the Wilmerding School of Industrial Arts in San Francisco, California. The first law formally authorizing such institutions was enacted in 1908. However, the idea took some time to catch on. The first four-year junior was established in Texas in 1923 as Hillsboro Junior College, known today as Hill College. Many others were established soon thereafter, but even in 1931, they numbered less than ten nationwide.The four-year junior college movement was closely associated with a broader movement for a 6-4-4 educational system: six years of elementary school, four years of junior high school, and four years of junior college (or "senior school"). Under this plan, graduation from junior college would "mark the end of the period of general education", and students who wished would then proceed to more specialized education leading to the bachelor's degree and beyond.Around its peak in 1942, the movement embraced 34 institutions nationwide, enrolling about 16,000 students in total. Five of these institutions and 8,000 of the students were in California. The development of the movement in California was facilitated by a state law allowing individual districts to adopt a 6-4-4 plan. Seven did so and established four-year public junior colleges: Pasadena (1928), Compton (1932), Ventura (1937), Pomona (1942), Napa (1942), Vallejo (1945), Stockton (1948). From the late 1940s to the early 1960s, all of these localities changed back to a traditional high-school system. The last holdout was Napa, which assimilated in 1964.

Four (Johan album)

Four-track

Four (Enneagram)

Four-to-the-floor

Mammalia

vertical

Four-year college

Four-thousand footers (sometimes abbreviated "4ks") is a term referring to a group of forty-eight mountains in New Hampshire at least 4,000 feet (1,219 meters) above sea level. To qualify for inclusion a peak must also meet the more technical criterion of topographic prominence important in the mountaineering sport of "peak-bagging".Most often, the term refers to the White Mountains Four Thousand Footers List established (and revised from time to time) by the Appalachian Mountain Club.

Sciurus hosei

Four (album)

Animalia

Four is the 4th studio album by Bleu. The album was part of a crowd funing campaign at kickstarter.com. The campaign funded about 40.000 $, which was far more than Bleu expected.Bleu said: "It's changed my whole world, I have a completely new outlook on my career and my life. It sounds dramatic, but it's really true."As a result of fans' contributions, he's been able to launch his own record label and put Four out himself in North America.

A. albiventris

Four (New York City Subway service)

Mean

Four-star general

Four-stroke cycle

Shine

Tony McKay

Four (stylized as four) is the breakthrough album by American band Blues Traveler, released on September 13, 1994.Four peaked at No. 8 on the Billboard 200 albums chart and is most known for its hits "Run-Around" and "Hook", which charted at Nos. 8 and 23, respectively, on the Billboard Hot 100. Both songs also charted in the top 20 on the Mainstream Rock and Modern Rock charts. According to the RIAA, the album is certified as 6× Platinum (6 million copies sold in the U.S.).

Four: A Divergent Story Collection

Four Aces (bridge)

Arthropoda

In physics, specifically for special relativity and general relativity, a four-tensor is an abbreviation for a tensor in a four-dimensional spacetime.

Intimacy

Jaquille Ksy

Four-star admiral

FourSquare

The Four Aces was a contract bridge team which dominated tournament play in the mid-thirties.

The four-toed elephant shrew or four-toed sengi is the only living species in the genus Petrodromus, which together with three other extant genera Rhynchocyon, Macroscelides and Elephantulus constitutes the order Macroscelidea. This species is only found in particular regions in Africa and is smaller in size compared to its relatives.

Four (Acts of Love)

Raiomond Mirza

Four-winged Saltbush

Four-sided dice, abbreviated d4, are often used in tabletop role-playing games to obtain random integers in the range 1–4. Two forms exist of this die: a tetrahedron (pyramid shape) with four equilateral triangle-shaped faces, and an elongated long die with four faces. The former type does not roll well and is thus usually thrown into the air or shaken in a box.

The exhaust power valve of a 2007 Honda CBR600RR.

Four Abstract Classicists

Four-striped grass mouse

Four-quark particle

FourCross

Four-stone handicap

Four-stroking

Four-wing saltbush

Four & More

Mullet Fever

Petrodromus tetradactylus tordayi

Four (drink)

Four-thirds

Rodentia

Four-spot Sylph

Four-thousander

Bleeker Ridge - Four.jpg

The Major Label

Four-year degree

India

Brother's Keeper

FourH

Four-sides model

Four-spotted ghost Moth

Four-square theorem

Obscene

Alright By Me

Four-striped Grass Rat

Classic Rock

Four-wheel steering

The Rolling Stone Album Guide

L. quadrimaculata

FourFourTwo is a thrice-weekly football magazine television show on Asian cable channel, Astro SuperSport, broadcasting to Malaysia and Brunei in association with global football magazine, FourFourTwo. In its third season, FourFourTwo has highlights from European leagues including England's Premier League, Spain's La Liga, Italian Serie A and the German Bundesliga.

Four-way cock

Lichtenstein, 1823

The Story of Love

Petrodromus tetradactylus

Where There's Smoke

Four-tensor

Four-wheel drive (4WD) has only been tried a handful of times in Formula One. In the World Championship era since 1950, only eight such cars are known to have been built.

God Made the Hammer
Delirium Tremens

Four (number)

FourDocs

Four-string guitar (disambiguation)

Four is a British independent film directed by John Langridge and released in 2011.

Four-wheel trails in Moab

A four-stroke power valve is a device fitted to four-stroke engines that constantly adjusts the internal diameter of the exhaust system to better suit engine speed. At low engine speeds the wave pressure within the pipe network is low. A full oscillation of the Helmholtz resonance occurs before the exhaust valve is closed, and to increase low-speed torque, large-amplitude exhaust pressure waves are artificially induced. This is achieved by partial closing of an internal butterfly valve within the exhaust at the point where the primary pipes from the cylinders join. This junction point essentially behaves as an artificial atmosphere. The alteration of the pressure at this point controls the behavior of reflected waves at this sudden increase in area discontinuity. Closing the valve increases the local pressure, inducing the formation of larger-amplitude negative reflected expansion waves. A servo motor controlled by the ECU opens and shuts the valve. The valve goes from being almost fully closed at idle speed, through to fully open at higher engine speeds. This ensures superior low to mid-range performance, more linear power output and reduced exhaust noise levels while the valve is in its reduced opening position.Yamaha was the first to develop such a system, called the Exhaust Ultimate Power Valve (EXUP). It first appeared on the Yamaha FZR EXUP and was later used on many other Yamahas.Later versions from Honda went by the names Honda Titanium Exhaust Valve (HTEV) and Honda Variable Intake/Exhaust (H-VIX), appearing on the CBR600RR and Honda CBR929RR. Suzuki's version is called Suzuki Exhaust Tuning (SET). The system is also used on the Triumph Daytona 675 triple.

Four-toed Tegu

Four-thousanders

A four-thousander is a mountain summit that is at least 4,000 metres above sea level. Because the highest peaks in Europe fall into this category, the summits of four-thousanders are popular in Europe with climbers and mountaineers as climbing goals. Although climbing these peaks does not require an expedition to be mounted, unlike the highest peaks in other continents, knowledge and experience of high altitude climbing is a pre-requisite for attempting these peaks.

Four (Fair Warning album)

Four (TV series)

The four-sides model (also known as communication square or four-ears model) is a communication model by Friedemann Schulz von Thun. According to this model every message has four facets though not the same emphasis might be put on each. The four sides of the message are fact, self-revealing, relationship, and appeal.

FourFourTwo is a thrice-weekly football magazine television show on Asian cable channel, Astro SuperSport, broadcasting to Malaysia and Brunei in association with global football magazine, FourFourTwo. In its third season, FourFourTwo has highlights from European leagues including England's Premier League, Spain's La Liga, Italian Serie A and the German Bundesliga. It is presented by former CNN and BBC anchor Jason Dasey and Malaysian-born anchor Adam Carruthers and co-hosted by Jay Menon, a former radio host. Its coverage of the Premier League includes a news update, fans segment and gossip section, with ex-England international Tony Cottee in London.

Four-striped Ground Squirrel

Four (TV Channel) NZ

Adrian Brown

Four-striped Damselfish

Four-wheel drive (disambiguation)

She Said

Four-term fallacy

Four-state bar code

Four is the first album by jazz saxophonist Joe Henderson released on the Verve label. It was recorded on April 21, 1968 and features a live performance by Henderson with Wynton Kelly, Paul Chambers and Jimmy Cobb. The Allmusic review by Scott Yanow states that "Henderson really pushes the rhythm section (which, although they had not played with the tenor previously, had been together for a decade) and he is certainly inspired by their presence.

Four-rotor Enigma

Four-star hotel

P. tetradactylus

Love

Coliseum
French Exit

Atelerix

Four (The Red Jumpsuit Apparatus album)

Four is a 2012 American independent feature film written and directed by Joshua Sanchez. It is based on the play of the same name by Christopher Shinn. The film stars Wendell Pierce, Emory Cohen, Aja Naomi King and E.J. Bonilla. The film premiered at the 2012 Los Angeles Film Festival where its ensemble cast won the top acting award. E.J. Bonilla received an Imagen Award nomination for his performance and Wendell Pierce received an Independent Spirit Award nomination for his performance.

Libellula quadrimaculata

FOUR

Four11.com

Four .jpg

The four-way valve or four-way cock is a fluid control valve whose body has four ports equally spaced round the valve chamber and the plug has two passages to connect adjacent ports. The plug may be cylindrical or tapered, or a ball.It has two flow positions as shown, and usually a central position where all ports are closed.It can be used to isolate and to simultaneously bypass a sampling cylinder installed on a pressurized water line. It is useful to take a fluid sample without affecting the pressure of a hydraulic system and to avoid degassing (no leak, no gas loss or air entry, no external contamination).It was used to control the flow of steam to the cylinder of early double-acting steam engines, such as those designed by Richard Trevithick. This use of the valve is possibly attributable to Denis Papin.Because the two "L"-shaped ports in the plug do not interconnect, the four-way valve is sometimes referred to as an "×" port.

FourTwoNine

group_or_band

Four (TV channel)

Four-string guitar

Love Alone

Four-toed Sengi

*Seps peronii

Four (novel)

Four-state barcode

Four-winged Mallee

A four-wire terminating set (4WTS) is a balanced transformer used to perform a conversion between four-wire and two-wire operation in telecommunication systems.For example, a 4-wire circuit may, by means of a 4-wire terminating set, be connected to a 2-wire telephone set.

Four-toed Rice Tenrec

Hood Shade

Save His Soul

Four-stroke-engine

Hymns

Four-spotted chaser

Four-stacker

Mick Harvey

A four-slide, also known as a multislide, multi-slide, or four-way, is a metalworking machine tool used in the high-volume manufacture of small stamped components from bar or wire stock. The press is most simply described as a horizontal stamping press that uses cams to control tools. The machine is used for progressive or transfer stamping operations.

yes
Album cover showing four thin circles within each other, coloured red, blue, yellow and green leading inwards, on a black background.

R. dilectus

The four-spotted chaser (Libellula quadrimaculata), known in North America as the four-spotted skimmer, is a dragonfly of the family Libellulidae found frequently throughout Europe, Asia, and North America.The adult stage is found between April to early September in the United Kingdom, and from mid-May to mid-August in Ireland. Larvae have a two-year developmental cycle. Adults feed predominantly on mosquitoes, gnats and midges; the larvae feed primarily on other aquatic insect larvae and on tadpoles.There is a variant form, praenubila Newman, which has exaggerated wing spots. This is believed to be related to water temperatures during larval development, and appears to be more common in Europe than in the Americas.The four-spotted skimmer is the state insect of Alaska.

note

Last Cigarette

Four-vectors

Four-toed earless skink

I Wish That I Were Stone

October 2011 – April 2012

Oryzorictes teradactylus

Four-vector

Go!

four11.com was a company that developed an Internet white pages directory for locating email addresses and collaborating using Internet phones, and videophones.It also developed RocketMail, one of the first major, free webmail services. For a brief time, RocketMail battled with Hotmail for the number-one spot among free webmail services. Four11, including RocketMail, was acquired by Yahoo! on October 8, 1997 for $92 million and used the RocketMail engine to create Yahoo! Mail.

Charlotte Church - FOUR.jpg

A four-year junior college was a type of educational institution in the United States in the 20th century that provided education from the 11th to the 14th grades, corresponding to the last two years of high school and the first two years of college.

Four-way valve

Four-source hypothesis

Four-wheeler

Four-spot midget

*Hemiergis peronii

So He Begins to Lie

Four (Foreigner album)

O. tetradactylus

Four-voice writing

Four-seam fastball

Four-stroke diesel engine

Based on a hymn by Bishop R. Heber

Four-wire telephone circuit

The Four-Step Impact Assessment is an academic framework initiated and published by Jonathan Mann and colleagues at the François-Xavier Bagnoud Center for Health and Human Rights at the Harvard School of Public Health. The assessment takes into account the negotiation of objectives between human rights and public health. Such an approach takes into account a measure of each discipline's respective overlap to expose infringement of goals. Such infringement or confluence can be mapped out in what Mann and colleagues proposed in a 2 by 2 table, as illustrated below.The Four-Step Impact Assessment:To what extent does the proposed policy or program represent “good public health”?Is the proposed policy or program respectful and protective of human rights?How can we achieve the best possible combination of public health and human rights quality?How serious is the public health problem?Is the proposed response likely to be effective?What are the severity, scope and duration of the burdens on human rights resulting from the proposed policy or program?To what extent is the proposed policy or program restrictive and intrusive?Is the proposed policy or program over inclusive or under inclusive?What procedural safeguards are included in the proposed policy or program?Will the proposed policy or program be periodically reviewed to assess both its public health effectiveness and its impact on human rights? Identify specific changes to the proposed policy or program that increase its human rights and/or public health quality while maintaining (or even strengthening) its public health effectiveness.Finally, does the proposed policy or program (as revised) still appear to be the optimal approach to the public health problem?As a way to visualize the intersection of both health and human rights, this table places Human Rights Quality on the Y-axis, and Public Health Quality on the X-axis. The levels or rank of both measures are graphically displayed at some point in the cartesian plane. The organizations that jointly supported this framework consisted of Mann’s Francois Xavier Bagnoud Center for Health and Human Rights, the International Federation of Red Cross, and Red Crescent Societies.

house, techno, electronica

Four-year junior college

IUCN3.1

four

Four-spotted chaser female P2.jpg

Four (comics)

Amazon MP3 bonus track

Four-square

Four is the 4th studio album by Bleu. The album was part of a crowd funing campaign at kickstarter.com. The campaign funded about 40.000 $, which was far more than Bleu expected.Bleu said: "It's changed my whole world, I have a completely new outlook on my career and my life. It sounds dramatic, but it's really true."As a result of fans' contributions, he's been able to launch his own record label and put Four out himself in North America. UK indie label Lojinx acquired the rights to release the "Four" in Europe. Bleu was stunned by the enthusiasm of his loyal fan base, "I was playing a show a couple of weeks ago and told everybody about the whole thing," he recalls. "I started crying onstage."Bleu recalls that the title for "Dead in the Mornin'" preceded the actual song by a fairly long stretch. "I was thinking about my mortality when I came up with the title, but I didn't want to write this melancholy dirge," he points out. "Then I thought, 'What if it's a big gospel rave-up?' When I think about my death, my funeral – which we all do – my great desire is that it'll be a celebration, a party. Everybody wants that New Orleans-style funeral. It IS the best way to send somebody off. It's personal, but tongue-in-cheek."The story-song "Singin' in Tongues" also contains what Bleu admits is a religious subtext: "It's not really about me," he relates, "but it does address the way music has saved me from total destruction. There's a lot of God in it."He acknowledges putting what he calls "a lot of weirdly morbid, upbeat stuff" on Four, noting various references to death (albeit mostly in high-energy rock settings) throughout. "Needless to say," he adds, "my mom's not too happy about it.""Like everyone else, I'm always grappling with these issues of death, God, the afterlife, my legacy – all the real things," Bleu adds of the album's themes. "That's reflected on this record; it's not just a bunch of love songs." Of course, the love songs it does include are choice, notably the exquisitely tender "In Love with My Lover" and the Lennon-esque, orchestral torch number "How Blue." As always, he insists, "I'm trying to find new angles on classic subjects."Official release of Four was on September 5, 2010 on the label "The Major Label".

Four (Blues Traveler album)

Four-stage Theory

In special relativity, a four-vector (also known as a 4-vector) is an object with four components, which transform in a specific way under Lorentz transformations. Specifically, a four-vector is an element of a four-dimensional vector space considered as a representation space of the standard representation of the Lorentz group, the (½,½) representation. It differs from a Euclidean vector in how its magnitude is determined. The transformations that preserve this magnitude are the Lorentz transformations, which include spatial rotations, boosts (a change by a constant velocity to another inertial reference frame).Four-vectors describe, for instance, position xμ in spacetime modeled as Minkowski space, a particle's four-momentum pμ, the amplitude of the electromagnetic four-potential Aμ(x) at a point x in spacetime, and the elements of the subspace spanned by the gamma matrices inside the Dirac algebra.The Lorentz group may be represented by 4×4 matrices Λ. The action of a Lorentz transformation on a general contravariant four-vector X (like the examples above), regarded as a column vector with Cartesian coordinates with respect to an inertial frame in the entries, is given by X ′ = Λ X , {\displaystyle X^{\prime }=\Lambda X,} (matrix multiplication) where the components of the primed object refer to the new frame. Related to the examples above that are given as contravariant vectors, there are also the corresponding covariant vectors xμ, pμ and Aμ(x). These transform according to the rule X ′ = ( Λ − 1 ) T X , {\displaystyle X^{\prime }={(\Lambda ^{-1})}^{\mathrm {T} }X,} where T denotes the matrix transpose. This rule is different from the above rule. It corresponds to the dual representation of the standard representation. However, for the Lorentz group the dual of any representation is equivalent to the original representation. Thus the objects with covariant indices are four-vectors as well.For an example of a well-behaved four-component object in special relativity that is not a four-vector, see bispinor. It is similarly defined, the difference being that the transformation rule under Lorentz transformations is given by a representation other than the standard representation. In this case, the rule reads X′ = Π(Λ)X, where Π(Λ) is a 4×4 matrix other than Λ. Similar remarks apply to objects with fewer or more components that are well-behaved under Lorentz transformations. These include scalars, spinors, tensors and spinor-tensors.The article considers four-vectors in the context of special relativity. Although the concept of four-vectors also extends to general relativity, some of the results stated in this article require modification in general relativity.

Pop, Rock

Team A

Four (Galliano album)

Four-slide

Four-track tape

Praise the Earth

Temminck & Schlegel in Von Siebold

Death and Mathematics
Entanglement

Four-spot roach

Studio
A Drop, An Ocean

A four-seam fastball, also called a rising fastball, a four-seamer, or a cross-seam fastball, is a pitch in baseball. It is a member of the fastball family of pitches and is usually the hardest (i.e., fastest) ball thrown by a pitcher. A few pitchers at the major league level can sometimes reach a pitch speed of up to 100 mph. Compare with the two-seam fastball.

Four:twenty Recordings

Four-spotted flounder

Four-spotted Ghost Moth

Kettling

Four-tensors

Under the Radar

Love Sick

L. hosei

Four-stroke engines

Four-vertex theorem

Sleep

FourPlay

Four-toed elephant shrew

Four (2012 film)

Grace Lane Studio and Atlantis Sound, Melbourne

Ratchet
mixed

Female, Kampinos Forest, Poland

Fuck the Facts, except where noted

FourText

Tschudi, 1838

Four-toed Elephant Shrew area.png

The Independent
favourable
Black Crown

Nesoryctes
Oryzorictes
Four-toed rice tenrec

Four-winged mallee

FourPlay String Quartet

A four-wire terminating set (4WTS) is a balanced transformer used to perform a conversion between four-wire and two-wire operation in telecommunication systems.For example, a 4-wire circuit may, by means of a 4-wire terminating set, be connected to a 2-wire telephone set. Also, a pair of 4-wire terminating sets may be used to introduce an intermediate 4-wire circuit into a 2-wire circuit, in which loop repeaters may be situated to amplify signals in each direction without positive feedback and oscillation.The 4WTS differs from a simple hybrid coil in being equipped to adjust its impedance to maximize return loss.Four-wire terminating sets were largely supplanted by resistance hybrids in the late 20th century.

The four-toed hedgehog (Atelerix albiventris), or African pygmy hedgehog, is a species of hedgehog found throughout much of central and eastern Africa.Populations tend to be scattered between suitable savannah or cropland habitats, avoiding forested areas. The species common name is derived from the number of toes found on its rear feet. Due to its extensive range and stable wild population, the species is rated as least concern by the IUCN. There are no universally agreed subspecies of A. albiventris.

A four-stroke power valve is a device fitted to four-stroke engines that constantly adjusts the internal diameter of the exhaust system to better suit engine speed. At low engine speeds the wave pressure within the pipe network is low. A full oscillation of the Helmholtz resonance occurs before the exhaust valve is closed, and to increase low-speed torque, large-amplitude exhaust pressure waves are artificially induced.

Little Movements

The four-square cipher is a manual symmetric encryption technique. It was invented by the famous French cryptographer Felix Delastelle.The technique encrypts pairs of letters (digraphs), and thus falls into a category of ciphers known as polygraphic substitution ciphers. This adds significant strength to the encryption when compared with monographic substitution ciphers which operate on single characters. The use of digraphs makes the four-square technique less susceptible to frequency analysis attacks, as the analysis must be done on 676 possible digraphs rather than just 26 for monographic substitution. The frequency analysis of digraphs is possible, but considerably more difficult - and it generally requires a much larger ciphertext in order to be useful.

iTunes Store bonus track

scutatum

Four (Suburban Kids with Biblical Names EP)

FourBall

Four11

Four-toed Mulch Skink

A. tetradactyla

Four-spiral semigroup

The Way Young Lovers Do

The Quietus

Four-striped ground squirrel

Four-star restaurant

The Four-Step Impact Assessment is an academic framework initiated and published by Jonathan Mann and colleagues at the François-Xavier Bagnoud Center for Health and Human Rights at the Harvard School of Public Health. The assessment takes into account the negotiation of objectives between human rights and public health. Such an approach takes into account a measure of each discipline's respective overlap to expose infringement of goals.

The four-toed salamander (Hemidactylium scutatum) is a lungless salamander native to eastern North America. It is a species of the monotypic genus Hemidactylium. (In Francophone Canada, it is called the salamandre à quatre orteils.)

Petrodromus

Four-wheel drive in Formula One

FOUR is the fourth extended play by Welsh recording artist Charlotte Church. It is the fourth in a series of five EPs released by Church. Her fourth alternative rock material, it was released on 10 March 2014 and was preceded by the lead single "Little Movements".

Four-wheel brakes

Four-star officer

Four (NZ)

Four-wheel bicycle

Straight On till Morning

Four % Universe

Four is the fourth studio album released by the hard rock band Fair Warning.

Bryan Senti
Theatrical Poster

Peters, 1846

Rustie Remix

Four-terminal sensing (4T sensing), 4-wire sensing, or 4-point probes method is an electrical impedance measuring technique that uses separate pairs of current-carrying and voltage-sensing electrodes to make more accurate measurements than the simpler and more usual two-terminal (2T) sensing. Four-terminal sensing is used in some ohmmeters and impedance analyzers, and in wiring for strain gauges and resistance thermometers.

Four (Beyoncé album)

Four (Bleu album)

United States

We Are Not Good People

Four-toed Hedgehog

Geographic range

Lean

The four-tube television camera, intended for color television studio use, was first developed by RCA in the early 1960s. In this camera, in addition to the usual complement of three tubes for the red, green and blue images, a fourth tube was included to provide luminance (black and white) detail of a scene.

FourWays

Four-terminal sensing (4T sensing), 4-wire sensing, or 4-point probes method is an electrical impedance measuring technique that uses separate pairs of current-carrying and voltage-sensing electrodes to make more accurate measurements than the simpler and more usual two-terminal (2T) sensing. Four-terminal sensing is used in some ohmmeters and impedance analyzers, and in wiring for strain gauges and resistance thermometers. Four-point probes are also used to measure sheet resistance of thin films.Separation of current and voltage electrodes eliminates the lead and contact resistance from the measurement. This is an advantage for precise measurement of low resistance values. For example, an LCR bridge instruction manual recommends the four-terminal technique for accurate measurement of resistance below 100 ohms.Four-terminal sensing is also known as Kelvin sensing, after William Thomson, Lord Kelvin, who invented the Kelvin bridge in 1861 to measure very low resistances using four-terminal sensing. Each two-wire connection can be called a Kelvin connection. A pair of contacts that is designed to connect a force-and-sense pair to a single terminal or lead simultaneously is called a Kelvin contact. A clip, often a crocodile clip, that connects a force-and-sense pair is called a Kelvin clip.

The 4 Aces is the quartet of passenger-cargo liners Excalibur, Exochorda, Exeter, and Excambion, originally built for American Export Lines by New York Shipbuilding of Camden, New Jersey between 1929 and 1931. AEL placed the "4 Aces" in service between the US and the Mediterranean, offering cruises of up to 40 days.During World War II, all four vessels were taken over by the U.S. Navy, renamed, and designated as AP- and APA-class troop transports. Excambion became USS John Penn (APA-23), Excalibur became USS Joseph Hewes (AP-50) and Exeter became USS Edward Rutledge (AP-52). These three of the original (pre-war) 4 Aces were ultimately lost to enemy action. The pre-war Exochorda was converted to military transport USS Harry Lee, later sold to Turkish Maritime Lines and renamed Tarsus.After World War II, American Export Lines purchased four C3-class Windsor-class attack transports built by Bethlehem Shipbuilding Corp. at Sparrow's Point, Maryland, had them refitted as passenger-cargo liners, and placed them in service as the new "4 Aces." USS Dauphin became Exochorda, USS Dutchess became Excalibur, USS Queens became Excambion and USS Shelby (APA-105) became Exeter. Carrying the names of the original quartet, the new "4 Aces" sailed under the AEL flag until the 1960s.In 1968, the post-war SS Exochorda was purchased by Stevens Institute of Technology in Hoboken, New Jersey to alleviate a shortage of on-campus student housing. It was refurbished at Bethlehem Steel Shipyard in Hoboken, renamed SS Stevens and anchored on the Hudson River adjacent to the campus where it served a dormitory. SS Stevens remained in service until 1975, when its continued operation became prohibitive due to skyrocketing utility costs. Before it was towed away and sold for scrap, one of Stevens' anchors was removed and permanently displayed [1] on campus as a memento of the institute's most popular dormitory.In 1965, the post-war Excambion became USTS Texas Clipper for service with the Texas Maritime Academy until being sunk as an artificial reef on November 17, 2007.The company's subsidiary American Export Airlines borrowed 3 of the names (excepting Exochorda) for its Sikorsky VS-44 flying boats, which it used in transatlantic service. Excambian is preserved on display at the New England Air Museum in Windsor Locks, Connecticut.[2]

Lariscus hosei

Four (New Zealand TV channel)

Pfeffer, 1896

Four-spin

Four Aces (passenger liners)

The four-toed hedgehog (Atelerix albiventris), or African pygmy hedgehog, is a species of hedgehog found throughout much of central and eastern Africa.Populations tend to be scattered between suitable savannah or cropland habitats, avoiding forested areas. The species common name is derived from the number of toes found on its rear feet. Due to its extensive range and stable wild population, the species is rated as least concern by the IUCN. There are no universally agreed subspecies of A.

Four-speed

Four-spotted Moth

Scarturus

May 2001

Four (Whigfield album)

Four-volume

Four Aces (Wild Cards)

This Is All

Four-terminal sensing

Four-wheel-drive

Four (cricket)

The four-way valve or four-way cock is a fluid control valve whose body has four ports equally spaced round the valve chamber and the plug has two passages to connect adjacent ports. The plug may be cylindrical or tapered, or a ball.It has two flow positions as shown, and usually a central position where all ports are closed.It can be used to isolate and to simultaneously bypass a sampling cylinder installed on a pressurized water line.

The four-square cipher is a manual symmetric encryption technique. It was invented by the famous French cryptographer Felix Delastelle.The technique encrypts pairs of letters (digraphs), and thus falls into a category of ciphers known as polygraphic substitution ciphers. This adds significant strength to the encryption when compared with monographic substitution ciphers which operate on single characters.

Four-wavevector

Paul Chronnell

Four-toed rice tenrec range

A promotional logo image of "Four".

Released

Four (Seaweed album)

Four-toed Elephant Shrew

Down Beat

Four (Joe Henderson album)

Four-spot sylph

Four Aces Club

The servo motor controls the valve via two cables. Shown removed.

Four-wheel vehicle

FourElevenFortyFour

Milne-Edwards & A. Grandidier, 1882

Summertime in New York

Album

Four-spotted clothes moth

Four-spotted orchis

Four-spotted Chaser

Four-tackle rule

Four-spine stickleback

Four-spotted Barb

Four-syllable idiom

Oryzorictes tetradactylus

Four-stroke

"Four Abstract Classists" was a landmark exhibition organized by Jules Langsner in 1959. The show featured the work of Karl Benjamin, Lorser Feitelson, Frederick Hammersley, and John McLaughlin. The term “abstract classicists” was coined in 1959 by Langsner to define these four southern California painters.

FourCC

studio

UK deluxe edition bonus disc

Untitled

Clash

A Watched Pot

Apurva Acharya

Four is the fourth studio album by British indie rock band Bloc Party. It was recorded in late 2011 and early 2012 at Stratosphere Sound, New York City, with producer Alex Newport. Newport also produced Wreckonomics—the EP of bassist Gordon Moakes' side project, Young Legionnaire. It was released on 20 August 2012 on independent label Frenchkiss Records, and was made available to stream the week preceding its release. The album peaked at number 3 in the UK Albums Chart, and at number 36 on the Billboard 200 chart in the United States. It is the last album featuring the original line-up with Gordon Moakes and Matt Tong.Despite four years of hiatus making this the largest gap between album releases, the band recorded the album using a more guitar-oriented sound, reminiscent of their debut album, Silent Alarm.

Four-year Sejm

Entertainment Weekly

Four-voice texture

Four-spotted Skimmer

English

R. bechuanae

Hemiergis

Four (Bloc Party album)

Four (film)

The four-striped ground squirrel (Lariscus hosei) is a species of rodent in the family Sciuridae. It is endemic to Borneo. Its natural habitat is subtropical or tropical dry forests. It is threatened by habitat loss.

Four is the first album by jazz saxophonist Joe Henderson released on the Verve label. It was recorded on April 21, 1968 and features a live performance by Henderson with Wynton Kelly, Paul Chambers and Jimmy Cobb. The Allmusic review by Scott Yanow states that "Henderson really pushes the rhythm section (which, although they had not played with the tenor previously, had been together for a decade) and he is certainly inspired by their presence. This is a frequently exciting performance by some of the modern bop greats of the era". Further selections from this concert were released as Straight, No Chaser.

Four-toed Terrapin

The Rolling Stone Jazz Record Guide

Fairy Dust

Four-spotted Butterflyfish

Four (Kumbia Kings album)

Lack of Imagination

Rhabdomys pumilio

Four-stroke cycle engine valves

Four (energy drink)

Four (channel)

Four is an Indian soap opera on SAB TV channel that aired every Monday to Friday at 8.30 p.m in India.

Four-way chess

FourChan

Four is the fourth studio album by British indie rock band Bloc Party. It was recorded in late 2011 and early 2012 at Stratosphere Sound, New York City, with producer Alex Newport. Newport also produced Wreckonomics—the EP of bassist Gordon Moakes' side project, Young Legionnaire. It was released on 20 August 2012 on independent label Frenchkiss Records, and was made available to stream the week preceding its release.

unknown

Four-sided dice

Rhabdomys

Allactaga

Four-wire terminating set

Four-toed Jerboa

Montreal

Four-rail electrification

Four-way

Day Four

The four-toed elephant shrew or four-toed sengi is the only living species in the genus Petrodromus, which together with three other extant genera Rhynchocyon, Macroscelides and Elephantulus constitutes the order Macroscelidea. This species is only found in particular regions in Africa and is smaller in size compared to its relatives. A comprehensive recording of this species is lacking.As its name suggests, the species has four toes on its hind feet, and like other elephant shrews, it has been named for its elephant-like, mobile proboscis.

Four-wave mixing (FWM) is an intermodulation phenomenon in non-linear optics, whereby interactions between two or three wavelengths produce two or one new wavelengths. It is similar to the third-order intercept point in electrical systems. Four-wave mixing can be compared to the intermodulation distortion in standard electrical systems. It is a parametric nonlinear process, in that the energy of the incoming photons is conserved.

*Lygosoma peroni [sic]

FourFourTwo (Australia)

FourPlay Electric String Quartet

Four (Hunter EP)

Four-room house

"Durgesh Nandinii" by

Four-wave mixing (FWM) is an intermodulation phenomenon in non-linear optics, whereby interactions between two or three wavelengths produce two or one new wavelengths. It is similar to the third-order intercept point in electrical systems. Four-wave mixing can be compared to the intermodulation distortion in standard electrical systems. It is a parametric nonlinear process, in that the energy of the incoming photons is conserved. FWM is a phase-sensitive process, in that the efficiency of the process is strongly affected by phase matching conditions.

Four-sided die

lower-roman

Four (New Zealand TV Channel)

Four 80 East

Four-thousand footers

United Kingdom

Four-wave mixing

Four-spotted yellowneck

The four-striped grass mouse or four-striped grass rat (Rhabdomys pumilio) is a species of rodent in the family Muridae.It is found throughout the southern half of Africa up to 2,300 metres (7,500 ft) above sea level, extending as far north as the Democratic Republic of the Congo. Its natural habitats are savannas, shrublands, Mediterranean-type shrubby vegetation, hot deserts, arable land, rural gardens, and urban areas.

Four-step impact assessment

Straight, No Chaser

Four-toed elephant shrew range

In mathematics, the four-spiral semigroup is a special semigroup generated by four idempotent elements. This special semigroup was first studied by Karl Byleen in a doctoral dissertation submitted to the University of Nebraska in 1977. It has several interesting properties: it is one of the most important examples of bi-simple but not completely-simple semigroups; it is also an important example of a fundamental regular semigroup; it is an indispensable building block of bisimple, idempotent-generated regular semigroups. A certain semigroup, called double four-spiral semigroup, generated by five idempotent elements has also been studied along with the four-spiral semigroup.

Tetragon

Oryzorictes tetradactylus range map.svg

FR CD 050

Hemidactylium

Four-winged saltbrush

Four-stroke Diesel cycle

Four (Seaweed Album)

Four (Dungen album)

Four-tonic system

Four (stylized as four) is the breakthrough album by American band Blues Traveler, released on September 13, 1994.Four peaked at No. 8 on the Billboard 200 albums chart and is most known for its hits "Run-Around" and "Hook", which charted at Nos. 8 and 23, respectively, on the Billboard Hot 100. Both songs also charted in the top 20 on the Mainstream Rock and Modern Rock charts. According to the RIAA, the album is certified as 6× Platinum (6 million copies sold in the U.S.). "Run-Around" won the 1995 Grammy Award for Best Rock Performance by a duo or group.

John Langridge

Four-spotted cockroach

In mathematics, the four-spiral semigroup is a special semigroup generated by four idempotent elements. This special semigroup was first studied by Karl Byleen in a doctoral dissertation submitted to the University of Nebraska in 1977.

I Feel Like I Belong

Four Aces (disambiguation)

Roach

Four-stroking is an operating condition of two-stroke engines, where they instead begin to fire every four strokes or more, rather than every two strokes. This firing is uneven, noisy and may even, in cases where it doesn't occur normally, damage the engine if allowed to continue unabated.However, in some circumstances, four-stroking is normal.

Four (The Verve album)

Discoing the Dead

Four-spotted ghost moth

FourThirds

Four-repeater rule

Four (2011 film)

The 4 Aces is the quartet of passenger-cargo liners Excalibur, Exochorda, Exeter, and Excambion, originally built for American Export Lines by New York Shipbuilding of Camden, New Jersey between 1929 and 1931. AEL placed the "4 Aces" in service between the US and the Mediterranean, offering cruises of up to 40 days.During World War II, all four vessels were taken over by the U.S. Navy, renamed, and designated as AP- and APA-class troop transports.

right

Ghetto Blaster Recordings

'Four' & More

Allactaga tetradactyla

Four-square cipher

Four-toed hedgehog

Four-row

Four-stroke Engine

Four-stroke power valve system

Range of A. albiventris

In special relativity, a four-vector (also known as a 4-vector) is an object with four components, which transform in a specific way under Lorentz transformations. Specifically, a four-vector is an element of a four-dimensional vector space considered as a representation space of the standard representation of the Lorentz group, the (½,½) representation. It differs from a Euclidean vector in how its magnitude is determined.

Gloger, 1841

Children of the Future

Four-toed Earless Skink

Four A's

V.A.L.I.S.

R. pumilio

Four-way key

left

Four-wing Saltbush

Four (Charlotte Church EP)

Four is the second studio album by the Canadian Hard rock band Bleeker Ridge. The album was released on June 4, 2013.

Four-spotted Ghost moth

Four-spotted Yellowneck

Four-stage Theory of the Republic of China

David Gutnik

Four Aces

Male

Four-spotted moth

The four-tube television camera, intended for color television studio use, was first developed by RCA in the early 1960s. In this camera, in addition to the usual complement of three tubes for the red, green and blue images, a fourth tube was included to provide luminance (black and white) detail of a scene. With such a camera, a sharp black and white picture was always assured, as it was not necessary to combine signals from the three colour tubes to provide the luminance detail.In the early days of colour television (from the mid 1950s to the early 1960s) studio cameras were heavy and hot-running because of the vacuum tube (thermionic valve) circuitry that they contained, in addition to three large image orthicon pick-up tubes. With these cameras there was always a tendency for the three coloured images to drift out of registration, over time, giving a consequential loss of picture sharpness.In 1962, in order to address these stability problems, RCA announced their prototype four-tube camera. The aims of the designers of the camera were, firstly, to produce a camera that was more tolerant to mis-registration and, secondly, to achieve a lighter camera by using smaller vidicon tubes to replace some of the large heavy IO tubes. The camera had an image orthicon tube for the luminance channel and three vidicon tubes for the colour channels. In addition, the camera was fully transistorized, apart from the four pick-up tubes. The camera went into full production in 1963 and sales of several hundred of the model were achieved over the next few years.In the mid 1960s, following RCA’s lead, other versions of the 4-tube cameras were produced (see below for details). In many cases, advantage was taken of a newly available pick-up tube (the Plumbicon). This new tube allowed cameras to be smaller and lighter than before.However, by the end of the decade, 4-tube cameras had fallen out of favour with most manufactures and customers. The picture quality and stability of pictures from 3-tube cameras had improved markedly, thanks to solid state circuitry, improvements in the Plumbicon tubes and the use of picture enhancement techniques. In addition, 3-tube cameras were smaller, lighter and cheaper than the 4-tube versions. By the early1970s, only a very few manufacturers still made cameras using the 4-tube format.

Livin' Like This

To Hell with You

Four (Matisse album)

Allactaga tetradactyla distribution.svg

Four (Gerling album)

Cover Four0ninE.jpg

Four-star level

peronii

Four-verse stanza

Midnight and the Ramparts

Four80east

center

Real Talk
The Healing

Four-striped Lipinia

The Music Box

Ben King

Four (Bleeker Ridge album)

Gregg Conde

Whisper Dependency

FourFourTwo (TV series)

Four-stroking is an operating condition of two-stroke engines, where they instead begin to fire every four strokes or more, rather than every two strokes. This firing is uneven, noisy and may even, in cases where it doesn't occur normally, damage the engine if allowed to continue unabated.However, in some circumstances, four-stroking is normal. When idling most two stroke engines will four-stroke, as well as when letting off the throttle.Four stroking will also occur in a correctly adjusted two stroke engine at full throttle without load. In the latter case this happens because the air-fuel mixture becomes overly rich and prevents the engine from running faster. The engine is intentionally constructed by the manufacturer for this to happen, as a too lean mixture will cause the engine to over-rev as well as overheat, and in engines running on premixed fuel a too lean mixture will cause poor lubrication. Running the engine at full throttle without load is not normally done in most applications, but in a chain saw the full throttle mixture is actually adjusted for the engine to four stroke at a given rpm set by the manufacturer. This is done by adjusting the high rpm screw on the carburetor while the engine runs at full throttle until the correct rpm level can be read on a tachometer.

Four-string banjo

Leaf Skeleton