Physical world and mathematics

Integrally closed domain

An integrally closed domain is an integral domain containing every element of its fraction field integral over it, that is, satisfying a monic polynomial over the domain.

Integrated assessment model

An integrated assessment model (IAM) is a computer model that links climate with economic, energy, and land-use systems to analyze climate policies, used in IPCC assessments.

Integrated Carbon Observation System

The Integrated Carbon Observation System (ICOS) is a pan-European research infrastructure, based in Helsinki since 2015, that provides standardized long-term data on the carbon cycle and greenhouse gas budget.

Integrated CO2 capture and conversion

Integrated CO2 capture and conversion, often abbreviated ICCC or ICCU, is a carbon management strategy that captures and converts CO2 into chemicals or fuels in one process.

Integrated differential phase contrast microscopy

Integrated differential phase contrast microscopy (iDPC-STEM) is an electron microscopy technique that reconstructs a sample's electrostatic potential from segmented-detector measurements, used to image light elements at low dose.

Integrated Forecasting System

The Integrated Forecasting System (IFS) is the numerical weather prediction suite with which ECMWF produces its operational forecasts, upgraded in regular numbered releases called cycles.

Integrated lithium niobate electro-optic frequency comb

An integrated lithium niobate electro-optic frequency comb is a chip-scale optical comb made by driving a lithium niobate modulator with a microwave signal, offering programmable spacing.

Integrated Multi-Satellite Retrievals for GPM

Integrated Multi-Satellite Retrievals for GPM (IMERG) is the unified U.S. algorithm for NASA's Global Precipitation Measurement mission, merging satellite and gauge data into half-hourly global precipitation fields since 2000.

Integrated multiport interferometer

An integrated multiport interferometer is a photonic chip-scale device that performs linear optical transformations between N input and N output ports using beam splitters and phase shifters.

Integrated nested Laplace approximations

Integrated nested Laplace approximations (INLA) is a deterministic method for approximate Bayesian inference in latent Gaussian models, introduced by Håvard Rue, Sara Martino, and Nicolas Chopin in 2009.

Integrated Ocean Drilling Program

The Integrated Ocean Drilling Program (IODP) was an international scientific ocean drilling program, co-led by the United States and Japan, that operated from 2003 to 2013.

Integrated photonic entanglement distribution

Integrated photonic entanglement distribution is the generation of entangled photon pairs on chip-scale photonic circuits and their transmission over fiber links, enabling quantum key distribution, teleportation, and sensing.

Integrated Public Use Microdata Series

The Integrated Public Use Microdata Series (IPUMS) is a family of harmonized census and survey microdata collections, maintained at the University of Minnesota since 1985, free to registered researchers.

Integrated quantum photonics

Integrated quantum photonics is the technology of generating, processing, and detecting quantum states of light on chip-scale photonic circuits, applied to quantum computing, simulation, and communication.

Integrated squeezed light source

An integrated squeezed light source is a chip-scale photonic device that generates squeezed light, typically using lithium niobate or silicon nitride, for sensing and quantum information applications.

Integrating factor

An integrating factor is a function that, when multiplied into a first-order ordinary differential equation, turns it into an exact equation whose solution follows from a potential function.

Integrating sphere

An integrating sphere is a hollow cavity with a diffuse, highly reflective coating whose multiple reflections produce uniform radiance, used to measure total light flux of lamps and LEDs.

Integration by parts

Integration by parts is an integral calculus technique that turns the integral of a product of functions into a boundary term minus an easier integral.

Integration by reduction formulae

Integration by reduction formulae is an integral calculus technique expressing an integral carrying a parameter n through a recurrence relation in terms of a similar integral with smaller n.

Integration by substitution

Integration by substitution, also called u-substitution, is a method for evaluating integrals by reversing the chain rule, rewriting them in terms of a new variable u.

Integrative literature review

An integrative literature review is a review methodology that combines experimental, non-experimental, theoretical, and empirical literature to generate new frameworks, following Whittemore and Knafl's 2005 five-stage process.

Integrative review

An integrative review is a research synthesis method that combines experimental, non-experimental, qualitative, and theoretical studies in a single review, widely used in nursing and health research.

Integrity Council for the Voluntary Carbon Market

The Integrity Council for the Voluntary Carbon Market (ICVCM) is an independent governance body that sets quality standards for the voluntary carbon market, publishing the Core Carbon Principles in July 2023.

Integro-differential equation

An integro-differential equation is an equation containing derivatives and integrals of the unknown function; its solution depends on accumulated history, not just local values, in models of memory, radiative transfer, and viscoelasticity.

Intelligence quotient

An intelligence quotient (IQ) is a standard measure of intelligence from psychological tests, introduced through Lewis Terman's Stanford revision and scaled so scores average 100.

Intelligibility (communication)

Speech intelligibility is the percentage of spoken speech a listener recognizes correctly, degraded by distance, background noise, reverberation, and hearing loss, and measured by metrics like STI and SII.

Intense pulsed light

Intense pulsed light (IPL), also known as intense pulsed light technology, is a non-laser treatment using a xenon flashlamp emitting broad-spectrum light pulses for hair removal, skin lesions, and dry eye.

Intension

Intension, also called intensionality, is the sense or internal content of a term, as opposed to its extension, the range of things the term applies to.

Intensity (physics)

Intensity in physics is the power a wave or beam carries per unit area, in watts per square meter; for light it equals the time-averaged Poynting vector, or irradiance.