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Meanings of minor planet names: 8001–9000
Meanings of minor planet names: 8001–9000 is the portion of the IAU's minor-planet naming record covering numbered objects 8001 through 9000, named mostly in the late 1990s and 2000s.
Meanings of minor-planet names
Meanings of minor-planet names are recorded by the IAU's Working Group Small Body Nomenclature, which approves each asteroid name, at most 16 characters, with a citation explaining its origin.
Meanings of minor-planet names: 1–1000
The list of meanings of minor-planet names 1–1000 covers the first thousand numbered minor planets, from 1 Ceres, discovered in 1801, to 1000 Piazzia, named in 1923.
Meanings of minor-planet names: 1001–2000
Meanings of minor-planet names: 1001–2000 is the naming record for the second thousand numbered minor planets, objects discovered chiefly photographically in the 1920s and 1930s and named afterward.
Measurable cardinal
A measurable cardinal is an uncountable cardinal carrying a nontrivial two-valued measure, introduced by Stanisław Ulam in 1930; its existence cannot be proved in ZFC and contradicts V = L.
Measurable function
A measurable function, also called a measurable map, is a function between measurable spaces that pulls measurable sets back to measurable sets, the functions that can be integrated.
Measurand
A measurand is the quantity intended to be measured, defined in the International Vocabulary of Metrology; it may differ from the quantity a measuring system actually engages.
Measure (mathematics)
In mathematics, a measure is a function assigning a nonnegative number or infinity to subsets of a set, generalizing length, area, and volume; measure theory underlies integration and probability.
Measure algebra
A measure algebra is a Boolean σ-algebra with a strictly positive measure, built from measurable sets identified when they differ only by a set of measure zero.
Measurement
Measurement is the process of experimentally obtaining one or more quantity values attributed to a quantity, such as mass or temperature; its study is called metrology.
Measurement bias
Measurement bias, also called bias, is the estimate of a systematic measurement error that stays constant or varies predictably across replicate measurements, unlike random error, and can be corrected by calibration.
Measurement in quantum mechanics
Measurement in quantum mechanics is the process whereby a quantum system coupled to a measuring device yields one outcome with probabilities given by the Born rule.
Measurement invariance testing
Measurement invariance testing is a psychometric procedure that checks whether a scale measures the same construct with the same parameters in different groups, using multigroup confirmatory factor analysis.
Measurement microphone calibration
Measurement microphone calibration determines a microphone's sound pressure sensitivity in V/Pa or dB relative to 1 V/Pa, using reciprocity, comparison, or newer laser-based methods, governed by IEC 61094.
Measurement model
A measurement model, also called a model of measurement, is the mathematical relation among all quantities involved in a measurement, used to calculate the value of the measurand.
Measurement of land in Punjab
Measurement of land in Punjab is the system of local units, such as the karam, marla, kanal, and bigha, used to state field areas in the Punjab region.
Measurement problem
The measurement problem is the central unresolved conceptual difficulty of quantum mechanics, arising because the Schrödinger equation predicts superpositions while measurements yield a single definite outcome.
Measurement repeatability
Measurement repeatability is the closeness of agreement between successive measurements of the same quantity under identical conditions, one of the two extremes of precision defined by ISO 5725, the other being reproducibility.
Measurement resolution
Measurement resolution is the smallest change in a measured quantity that causes a perceptible change in an instrument's indication, distinct from accuracy and precision.
Measurement system analysis
Measurement system analysis (MSA) is the statistical evaluation of a measurement process, best known for its Gauge R&R study, which separates repeatability, reproducibility, and part-to-part variation in manufacturing.
Measurement systems analysis
Measurement systems analysis (MSA) is the statistical study of a measurement process that identifies and quantifies its sources of variability; its best-known tool is the Gauge R&R study.
Measurement uncertainty
Measurement uncertainty is the parameter, usually a standard deviation or stated interval, characterizing the dispersion of values attributed to a measurand, the quantity intended to be measured.
Measurement-device-independent quantum key distribution
Measurement-device-independent quantum key distribution (MDI-QKD) is a quantum key distribution protocol proposed in 2012 by Lo, Curty, and Qi, in which Alice and Bob send states to an untrusted relay.
Measurement-induced phase transition
A measurement-induced phase transition (MIPT) is a nonequilibrium phase transition in monitored quantum many-body systems, identified in random quantum circuits starting in 2018 and 2019.
Measurement-only quantum error correction
Measurement-only quantum error correction protects quantum information by recording measured errors in a classical Pauli frame instead of applying physical corrections, an approach traced to Emanuel Knill's 2005 work.
Measures of national income and output
Measures of national income and output, chiefly GDP, are national accounting statistics quantifying an economy's production, income, and expenditure under the System of National Accounts.
Measuring cup
A measuring cup, or measuring jug, is a kitchen utensil with graduated markings for measuring ingredients by volume, holding 8 fluid ounces in the United States.
Mecamylamine
Mecamylamine (Inversine, Vecamyl) is a drug that blocks nicotinic acetylcholine receptors, introduced in the 1950s as the first orally available antihypertensive and now used mainly as a research tool.
Mechanical activation
Mechanical activation is a solid-state processing method that uses milling or grinding to store energy in solids as defects, raising reactivity in later chemical steps.
Mechanical advantage device
A mechanical advantage device is a mechanism, typically a simple machine like a lever, pulley, or inclined plane, that multiplies input force at the cost of greater distance.