Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Qua"

Quad

A four-wheeled off-road ATV which is generally designed for one rider.
Either four insulated conductors twisted together (star-quad) or two twisted pairs (twin-quad). Normally a single structural unit of a multiconductor cable.
A prefix to denote an object with four components

Quad Cab: Dodge's term for a crew cab (i.e., a pickup truck with four doors)

Quad-cam engine: An engine with four camshafts

Quad fork: Quad fork

A steering device which attaches to the rim of the steering wheel to assist disabled drivers in handling the steering.

Quadrant

The Gearshift selector indicator marked PRNDL.
The V-shaped toothed section of a worm-and-sector steering box.
A slotted segmental guide through which an adjusting lever works. It is provided with means for locating the lever in a number of angular positions.
A quarter of a circle.

Quadrant dividers: A form of divider in which one limb moves over an arc fixed rigidly to the second limb and may be secured to it by tightening a binding screw

Quadraphonics: See
Quadrophonics

Quadratic equation: An algebraic equation of the second degree (ax² + bx + c = 0), whose solution is

Quadrature: The relation between two waves of the same frequency but one-quarter of a cycle (90°) out of phase, as in TV color difference signals

Quadrature amplitude modulation: A modulation system involving phase and amplitude modulation of a carrier, used in microwave and satellite communication links.

Quadrature reactance: A term used in the two reaction theory of synchronous machines to denote the ratio which the synchronous reactance drop produced by the quadrature component of the armature current bears to actual value of quadrature component.

Quadrature transformer: A transformer designed so that secondary emf is 90° displaced from primary emf

Quadricycle: An early type of lightweight, four-wheeled automobile using bicycle wheels and a frame of steel tubes.

Quadrilateral: A four-sided polygon

Quadrilateral speed-time curve: A simplified form of speed-time curve used in making preliminary calculations regarding energy consumption and average speed of railway trains. The acceleration and coasting portions of the curve are sloping straight lines and the braking portion is neglected, so that the curve becomes a quadrilateral

Quadripole: A network with two input and two output terminals. A balanced wave-filter section

Quadrivalent: A term describing an atom with four electrons in its valency shell

Quadrophonics: A system of sound transmission using a minimum of four speakers fed by four, or sometimes three, separate channels.

Quadruple-expansion engine: A steam engine in which the steam is expanded successively in four cylinders of increasing size, all working on the same crankshaft

Quadruple point: A point on a concentration-pressure-temperature diagram at which a two-component system can exist in four phases

Quadruplex: Videotape recording and reproduction system using four rotating heads to produce transverse tracks on two-inch wide magnetic tape

Quadruplex system: A system of Morse telegraphy arranged for simultaneous independent transmission of two messages in each direction over a single circuit

Quadrupole: A collection of charges such that the potential at a point distance r from their center of mass may be expressed by an infinite series of terms in inverse powers of r. The inverse third power term is the quadrupole potential

Quadrupole moment: The moment derived from the series expansion of charges multiplied by space co-ordinates. The sum of the quadratic terms is the quadrupole moment, which is possessed by most metals.
Also see
Quadrupole

Quadrupoles: Radiator producing a sound field of two adjacent dipoles in antiphase. the eddies in a subsonic jet of gas are quadrupoles

Qualification test: An evaluation of a flight article or its equivalent to verify that it functions correctly under the specified conditions of space-flight; normally the test conditions are more severe than those expected

Qualitative analysis: Identification of the constituents of a sample without regard to their relative amounts. It often refers to elemental analysis, but may also refer to the detection of acid-base or redox properties in a sample

Quality

Conformance to requirements in relation to a degree of excellence.
In sound reproduction, the degree to which a sample of reproduced sound resembles a sample of the original sound. The general description of freedom from various types of acoustic distortion in sound-reproducing systems.
The timbre or quality of a note which depends upon the number and magnitude of harmonics of the fundamental.
The condition of a saturated vapor, particularly steam, expressed as the ratio per cent of the vaporized portion to the total weight of liquid and vapor.
In radiography, an indication of the approximate penetrating power. Higher voltages produce higher quality X-rays of shorter wavelength and greater penetration. The term dates from before the nature of X-rays was completely understood.
Also see
Air Quality
Build quality

Quality control: A form of inspection involving sampling of parts in a mathematical manner to determine whether or not the entire production run is acceptable, a specified number of defective parts being permissible

Quality factor: A measure of relative biological effectiveness.

Quality grading: Department of Transportation requirements for labeling of various tire safety and performance criteria by the manufacturer.

Quality level: See
Acceptable quality level

Quality management: See
Total quality management

Quality Management District: See
Air Quality Management District

Quality of service: The overall performance level of a network connection as perceived by its users, covering such aspects as speech quality, digital error rate and delay jitter.

Quality Standards: See
National Ambient Air Quality Standards

Quality systems: Ways of managing materials, components and products so as to ensure high-quality control of manufactured products at all levels

Quantile: The argument of the cumulative distribution function corresponding to a specified probability; (of a sample) the value below which occur a specified proportion of the observations in the ordered set of observations.

QuantiMet: A trade name for a machine which analyses material surfaces for microstructural variables such as grain size diameter, orientation etc. Based originally on the optical microscope, extended to electron optical examination. Uses computer techniques to perform statistical analyses based on stereological methods.

Quantitative analysis: Identification of the relative amounts of substances making up a sample. It usually refers to elemental analysis, but may refer to any constituent of the sample. In addition to chemical methods, virtually every physical property can be a basis for some analytical method, and spectroscopic and electrochemical techniques are particularly often employed.

Quantity of electricity: A product of the flow of electricity (current) and time during which it flows. The term may also refer to a charge of electricity.

Quantity of light: A product of luminous flux and time during which it is maintained; usually stated in lumen-hours.

Quantity of radiation: Product of intensity and time of X-ray radiation. Not measured by energy, but by energy density and a coefficient depending on ability to cause ionization.

Quantity surveyor: One who measures up from drawings and prepares a bill (or schedule) of quantities showing the content of each item. This is then used by contractors for estimating. The quantity surveyor also periodically measures and assesses the value of the work done.

Quantization

In quantum theory, the division of energy of a system into discrete units (quanta), so that continuous infinitesimal changes are excluded.
In Pulse-code modulation, the division of the amplitude range of a continuously variable signal, e.g., speech or video, into discrete levels for the purposes of sampling and coding.

Quantization distortion: The distortion that arises in the mapping of a continuous signal on to a number of discrete levels so that it may be coded for digital transmission.

Quantization distortion unit: A measure of Quantization distortion equivalent to the transition from analogue to 64 Kbits-^-1 A-law digital code and back again.

Quantization noise: Noise introduced into a circuit using Pulse-code modulation because there are too few levels of quantitation to describe the waveform accurately.

Quantometer: An instrument showing by spectrographical analysis the percentages of the various metals present in a metallic sample.

Quantum

A general term for the indivisible unit of any form of physical energy; in particular the photon, the discrete amount of electromagnetic radiation energy, its magnitude being hv where v is the frequency and h is Planck's constant.
An interval on a measuring scale, fractions of which are considered insignificant.

Quantum chromodynamics: (QCD) The theory of strong interactions between elementary particles including the interaction that binds protons and neutrons to form a nucleus. It assumes that strongly interacting particles are made of quarks and that gluons bind the quarks together.

Quantum efficiency: The number of electrons released in a photocell per photon of incident radiation of specified wavelength.

Quantum electrodynamics: (QED) A relativistic quantum theory of electromagnetic interactions. It provides a description of the interaction of electrons, muons and photons and hence the underlying theory of all electromagnetic phenomena.

Quantum electronics: The study of the amplification or generation of microwave power in solid crystals, governed by quantum mechanical laws.

Quantum field theory: The overall theory of fundamental particles and their interactions. Each type of particle is represented by appropriate operators which obey certain commutation laws. Particles are the quanta of fields in the same way as photons are the quanta of the electromagnetic field. So gluon fields and Intermediate vector boson fields can be related to strong and weak interactions. Quantum field theory accounts for the Lamb shift.

Quantum gravity: The theory that would unify gravitational physics with modern Quantum field theory.

Quantum Hall effect: The effect in which Hall resistivity changes by steps so that it is a fraction of h/e² where h is Planck's constant and e is the electronic charge. Observed in two-dimensional semiconductors (e.g., Metal-oxide-silicon) at high magnetic fields and ultra-low temperatures.
Also see
Hall effect.

Quantum mechanics: A generally accepted theory replacing classical mechanics for microscopic phenomena. Quantum mechanics also gives results consistent with classical mechanics for macroscopic phenomena. Two equivalent formalisms have been developed matrix mechanics (developed by W. Heisenberg) and wave mechanics (developed by E. Schrödinger). The theory accounts for a very wide range of physical phenomena.

Quantum number: One of a set of numbers describing possible quantum states of a system, e.g., nuclear spin.

Quantum statistics: Statistics of the distribution of particles of a specified type in relation to their energies, the latter being quantized.

Quantum theory: The theory developed from Planck's law to account for black-body radiation, the Photoelectric effect and the Compton effect and to form the Bohr model of the atom and its modification by Sommerfeld.

Quantum voltage: Voltage through which an electron must be accelerated to acquire the energy corresponding to a particular quantum

Quantum wire: A nano-structure proportioned like a wire so that electron behavior is strongly constrained by quantum mechanical effects in two dimensions.

Quantum yield: The ratio of the number of photon-induced reactions occurring to the total number of incident photons.

Quaquaversal fold: A dome-like structure of folded sedimentary rocks which dip uniformly outward from a central point.

Quark: A type of fundamental particle that forms the constituents of Hadrons. There are currently believed to be six types (or Flavors) of quarks (and their antiquarks) up, down, charm, strange, top, bottom. In quark theory, the baryon is composed of three quarks of different color, an antibaryon is composed of three antiquarks, and a meson is composed of a quark and an antiquark. No quark has been observed in isolation.

Quarl: See
Burner firing block

Quarrel: The diamond-shaped pane of glass used in Fret-work

Quarries: Same as Quarry tiles

Quarry

An open working or pit for granite, building-stone, slate or other rock.
An underground working in a coal mine for stone to fill the goaf. Distinction between quarry and mine is somewhat blurred in law, but usage implies surface workings.

Quarry-faced: A term applied to a building-stone whose face is hammer-dressed before leaving the quarry.

Quarry-pitched: A term applied to stones which are roughly squared before leaving the quarry.

Quarry stone bond: A term applied to the arrangement of stones in rubble masonry.

Quarry tile: The common unglazed, machine-made paving tile not less than .75" (20 mm) in thickness, Also called promenade tile.

Quart: One-quarter of a gallon, or two pints (UK 1.14 liter, US 0.946 liter in liquid measure, 1.1 liter in dry measure).

Quarter

The phase of the Moon at quadrature. The first quarter occurs when the longitude of the Moon exceeds that of the Sun by 90°, the last quarter when the excess is 270°. The two other quarters are the new Moon and full Moon.
The fourth part of a hundredweight, equivalent to 28 (or in US 25) pounds avoirdupois.
A unit equal to 8 bushels.

Also See
Blind Quarter
Hinged quarter window

Quarter bend: A union connecting two pipes at 90°

Quarter bond: The ordinary brickwork bond obtained by using a 2.25" (57 mm) closer.

Quarter-bound: A term applied to a book having its back and part of its sides covered in one material and the rest of its sides in another.

Quarter bumper: A type of shortened bumper designed to give a car a sporting image. Instead of extending around the full width of the car, short bumper sections around the left-hand and right-hand corners leave the center unprotected. This type of bumper was popular on certain sports models manufactured by Opel and Ford in the 1970s

Quarter-chord point: The point on the Chord line at one quarter of the chord length behind the leading edge. Sweepback is usually quoted by the angle between the line of the quarter-chord points and the normal to the aircraft fore-and-aft center-line.

Quarter-elliptic leaf spring: A cantilevered half of a semi-elliptic leaf spring, rigidly attached to a vehicle at its major section and carrying the axle at its end section

Quarter-inch cartridge: (QIC) A standard for computer tapes.

Quartering: A method of obtaining a representative sample for analysis or test of an aggregate with occasional shovelsful, of which a heap or cone is formed, This is flattened out and two opposite quarter parts are rejected. Another cone is formed from the remainder which is again quartered, the process being repeated until a sample of the required size is left.

Quarter light

A small, roughly triangular, front-door window that swings out on fixed hinges; situated in front of and separate from the main window.
A small, roughly triangular window situated behind the main rear-door window

Quarter light filler panel: A relatively small, roughly triangular panel, usually black, inserted into the rear side-window's rear bottom corner

Quarter lines: The aggregation of waterlines, buttocklines, sections and diagonals indicative of a ship's form, drawn on a scale of .25" = 1 ft.
Also see
Fairing

Quarter page folder: A supplementary device to give a third fold in line with the run of the paper on webfed presses.

Quarter panel: A rear section of the body shell which incorporates the rear fender and usually also the C-pillar. In modern car bodies, the rear fender usually is no longer a separate welded or bolt-on panel, Instead it blends smoothly into the bottom of the rear window frame and the rear panel
Also see
Rear Quarter Panel

Quarter-phase systems: See
Two-phase systems.

Quarters: Accommodations (i.e., a place where occupants of a ship can stay).

Quarter-space landing: A landing extending across only half the width of a staircase.

Quarter turn: A wreath subtending an angle of 90°

Quarter-wave antenna: One whose overall length is approximately a quarter of free-space wavelength corresponding to frequency of operation. Under these conditions it is oscillating in its first natural mode, and is half a dipole.

Quarter-wave bar: See
Quarter-wave line

Quarter-wavelength stub: Resonating two-wire or coaxial line, approximately one quarter-wavelength long, of high impedance at resonance. Used in antennas, as insulating support for another line, and as a coupling element.

Quarter-wave line: Quarter-wavelength section of transmission line designed to operate as a matching device between lines of different impedance levels.

Quarter-wave plate: A plate of quartz, cut parallel to the optic axis, of such thickness that a retardation of a quarter of a period is produced between ordinary and extraordinary rays traveling normally through the plate. By using a quarter-wave plate, with its axis at 45° to the axes of a polarizer, circularly polarized light is obtained.

Quarter window

A small, roughly triangular, front-door window that swings out on fixed hinges; situated in front of and separate from the main window.
A small, roughly triangular window situated behind the main rear-door window.

Also See
Hinged quarter window

Quarter window filler panel: A relatively small, roughly triangular panel, usually black, inserted into the rear side-window's rear bottom corner

Quartic equation: An algebraic equation of the fourth degree, i.e., ax₄+bx₃+cx₂+dx+e=0. Its resolution into a pair of quadratic equations, and hence its solution, depends upon the solution of a subsidiary cubic equation.

Quartile: The argument of the cumulative distribution function corresponding to a probability of either 1/4 (first or lower quartile) or 3/4 (third or upper quartile); (of a sample) the value below which occurs a quarter (first or lower quartile) or three-quarters (third or upper quartile) of the observations in the ordered set of observations.

Quarto: The quarter of a sheet, or a sheet folded twice to make four leaves or eight pages; written 4to.

Quartz: Crystalline silica, SiO₂, occurring either in prisms capped by rhombohedra (low-temperature quartz, stable up to 573°C) or in hexagonal bipyramidal crystals (high-temperature quartz, stable above 573°C). Widely distributed in rocks of all kinds; igneous, metamorphic and sedimentary; usually colorless and transparent (rock crystal), but often colored by minute quantities of impurities as in citrine, cairngorm, etc; also finely crystalline in the several forms of chalcedony, jasper etc.

Quartz crystal: A disk or rod cut in the appropriate directions from a specimen of piezoelectric quartz, and accurately ground so that its natural resonance shall occur at a particular frequency.

Quartz-diorite: A coarse-grained holo-crystalline igneous rock of intermediate composition, composed of quartz, plagioclase feldspar, hornblende and biotite, and thus intermediate in mineral composition between typical diorite and granite.

Quartz-dolerite: A variety of dolerite which contains interstitial quartz usually intergrown graphically with feldspar, forming patches of micropegmatite. A dyke-rock of worldwide distribution, well represented by the Whin Sill rock in N. England.

Quartz-fiber balance: A very sensitive spring balance, the spring being a quartz fiber

Quartz-fiber electroscope: A personal radiation monitor whose state can be viewed at any time. The fiber is charged periodically and discharged by radiation.

Quartz halogen bulb: See
Quartz-halogen bulb.

Quartz-halogen bulb: A Bulb with an inner quartz Bulb which holds a tungsten Filament. Usually the inner Bulb contains an inert gas such as iodine or one of the other five halogen gases. The use of a halogen gas prevents the Bulb from turning black and thus reducing the amount of light output. Because this type of Bulb requires intense heat, a quartz inner Bulb is needed instead of glass. As a result, the quartz-halogen Bulb produces more light per watt of electrical power. When replacing a quartz-halogen Bulb, it is important not to touch the outer Bulb with your fingers. The moisture and oils deposited on the glass will cause the glass to break under the high temperature.

Quartz-iodine lamp: A compact high-intensity light source, consisting of a bulb with a tungsten filament, filled with an inert gas containing iodine (sometimes bromine) vapor. The bulb is of quartz, glass being unable to withstand the high operating temperature (600°C). Used for vehicle-lamps, cine projectors etc.

Quartzite: The characteristic product of the metamorphism of a siliceous sandstone or grit. The term is also used to denote sandstones and grits which have been cemented by silica.

Quartz-keratophyre: A type of soda-trachyte carrying accessory quartz.

Quartz lamp: One which contains a mercury arc under pressure, a powerful source of ultraviolet radiation.

Quartz oscillator: One whose oscilliation frequency is controlled by a piezoelectric quartz crystal.

Quartz porphyrite: A porphyrite carrying quartz as an accessory constituent; the representative in the medium grain-size group of the fine-grained dacite.

Quartz porphyry: A medium-grained igneous rock of granitic composition occurring normally as minor intrusions, and carrying prominent phenocrysts of quartz.

Quartz resonator: A standard of frequency comparison making use of the sharply resonant properties of a piezoelectric quartz crystal.

Quartz topaz

Quartz tuning system: (QTS) quartz-controlled tuning system with digital tuning and frequency display; uses microprocessor-controlled PLL circuitry

Quartz wedge: A thin wedge of quartz which provides a means of superposing any required thickness of quartz on a mineral section being viewed under a polarming microscope, the wedge being cut parallel to the optic axis of a prism of quartz crystal. It enables the sign of the birefringence of biaxial minerals to be determined from their interference figure in convergent light.

Quartz wind: A form of acoustic streaming near ultrasonic transducers operated at high amplitudes

Quasar: A distant, compact, object far beyond our Galaxy which looks star-like on a photograph but has a red shift characteristic of an extremely remote object.

Quasi-biennial oscillation: (QBO) Alternation of easterly and westerly wind regimes in the equatorial stratosphere with an interval between successive corresponding maxima of from 24 to 30 months. A new regime starts above 30 km and propagates downward at about 1 km per month.

Quasi-bistable circuit: An astable circuit which is triggered at a high rate as compared with its natural frequency.

Quasi-duplex: A circuit which operates apparently duplex, but actually functions in only one direction at a time, e.g., a long distance telephone or a radio link, which is automatically switched by speech.

Quasi-elastic method: A method of stress analysis for non-linear and/or time-dependent materials, especially polymers, in which elastic moduli in the elastic equations are replaced by the values of the corresponding secant modulus or creep modulus, at the required levels of strain or time, respectively.

Quasi-Fermi levels: Energy levels in a semi-conductor from which the number of electrons or holes available for conduction under nonequilibrium conditions; esp. when light is falling on the semiconductor, can be calculated in the same way as from the true Fermi level which applies under equilibrium conditions.

Quasi-geostrophic approximation: An approximation to the dynamical equations governing atmospheric flow, esp. the vorticity equation, whereby the horizontal wind is replaced by the geostrophic wind in the term representing the vorticity, but not in the term representing the divergence.

Quasi-longitudinal wave: A special type of wave occurring in plates and bars. The particle motion is mainly longitudinal and has a small transverse component caused by lateral contraction.

Quasi-optical waves: Invisible electromagnetic waves with similar wavelength and laws of propagation to visible light.

Quasi-stationary front: A weather front which is moving slowly and irregularly so that it cannot be described as either a cold front or a warm front.

Quasi S-VHS playback: The facility for playing S-VHS tapes in a VHS video recorder - with VHS resolution.

Quaternary

A chemical term consisting of four components etc.; also, connected to four non-hydrogen atoms.
The geological period which succeeded the Tertiary. It includes the Pleistocene and Holocene epochs and covers a time span of approx the last two million years.

Quaternary ammonium bases: Bases derived from the hypothetical ammonium hydroxide NH₄OH, in which the four hydrogen atoms attached to the nitrogen are replaced by alkyl radicals, e.g.,
(C₂H₅)₄NOH, tetraethyl-ammonium hydroxide.

Quaternary diagram: Phase diagram of four-component system.

Quaternary phaseshift keying: Used in microwave links and satellite communications to double the channel capacity of conventional binary phase-shift keying without changing the bandwidth. The phase of the carrier can be set by modulation to any one of four positions.

Quattro: An Italian term for four and indicates that a car has four-wheel drive