Technology and the built world

Residential gateway

A residential gateway, also called a home gateway or home router, is the single device an ISP provides that combines modem, routing, and Wi-Fi functions for a household.

Residenz (Würzburg)

The Würzburg Residence is the Baroque palace of the prince-bishops of Würzburg in southern Germany, begun in 1720, designed by Balthasar Neumann, and decorated by Tiepolo.

Residenzschloss (Munich)

The Residenzschloss, known in English as the Munich Residence (Münchner Residenz), is the former palace of the Bavarian Wittelsbach rulers in central Munich, used from 1508 to 1918.

A residual dense network (RDN) is a convolutional neural network architecture for image restoration, introduced by Yulun Zhang and colleagues at CVPR 2018 for super-resolution, denoising, and deblurring.

Residual learning

Residual learning is a neural network training approach where each block learns a correction added to its input through a shortcut, enabling 152-layer networks that won ILSVRC 2015.

Residual neural network

A residual neural network (ResNet) is a deep neural network whose layers learn residual functions via identity shortcuts, introduced by Kaiming He's team at Microsoft Research and winning ILSVRC 2015.

Residual policy learning

Residual policy learning (RPL) is a robot-learning method in which a reinforcement learning policy learns a corrective residual added to an existing baseline controller, introduced in December 2018.

Residual reinforcement learning

Residual reinforcement learning is a robot-control method in which a learned policy adds corrections to a fixed base controller, keeping its reliability while learning fixes its weaknesses.

Residual shear strength

Residual shear strength is the minimum, constant shear strength a soil reaches after large displacement, when platy clay particles orient face-to-face along the shear surface.

Residual stream

The residual stream is the shared, accumulating state vector through which every transformer component communicates, a 2021 framing that became the standard lens of mechanistic interpretability.

Residual stress

Residual stress is stress that remains locked in a material after all external loads are removed, arising from welding, machining, and heat treatment and affecting fatigue life and cracking.

Residual stress analysis

Residual stress analysis is the family of techniques for measuring stresses left inside a component after manufacturing or loading, by destructive strain-release or diffraction methods.

Residual vector quantization

Residual vector quantization, also called multi-stage vector quantization, is a compression method that quantizes a vector and its successive residuals with a chain of codebooks.

Residual-current device

A residual-current device (RCD), also called a ground fault circuit interrupter, disconnects a circuit when current imbalance exceeds a threshold such as 30 mA, protecting people from electric shock.

Residue hydroconversion

Residue hydroconversion is the catalytic upgrading of petroleum residua, the heavy bottoms of crude distillation, with hydrogen, converting heavy molecules into lighter fractions while removing sulfur, nitrogen, and metals.

Resilience (lander)

Resilience was a Japanese lunar lander built by ispace, launched in January 2025 and destroyed in a June 2025 landing attempt after a faulty laser rangefinder.

Resilience engineering

Resilience engineering is a field of safety science and systems engineering studying how complex socio-technical systems, such as hospitals and railways, sustain operations during disturbances.

Resilient Lady

Resilient Lady is an adults-only cruise ship operated by Virgin Voyages, built by Fincantieri and delivered in 2022 as the third of four Lady Ships.

Resilient modulus

The resilient modulus (MR) is the ratio of applied cyclic stress to recoverable strain in unbound pavement materials and subgrade soils, the key material input in modern pavement design.

Resilient Pharmaceuticals

Resilient Pharmaceuticals, formerly Lykos Therapeutics and the MAPS Public Benefit Corporation, is an American company developing MDMA-assisted therapy for PTSD, which the FDA rejected in August 2024.

Resin identification code

A resin identification code (RIC) is the numbered triangle marking on plastic articles that identifies the resin used, developed in 1988 and administered by ASTM International since 2008.

Resin transfer molding

Resin transfer molding (RTM) is a closed-mold process that makes fiber-reinforced composites by injecting liquid resin into a mold around a dry preform, used in aerospace and automotive manufacturing.

Resin-in-leach

Resin-in-leach (RIL) is a hydrometallurgical process for recovering gold in which ion exchange resin beads are added to the cyanide leach slurry, so adsorption and leaching occur in the same tanks.

Resistance welding

Resistance welding is a group of joining processes that presses metal parts together and passes current through them, heating the joint by its own resistance.

Oct 22, 2026

Resistive switching

Resistive switching is the reversible change of a thin insulating film's resistance under applied voltage between two electrodes, letting two-terminal devices such as RRAM store data as resistance states.

Resistive tactile sensor

A resistive tactile sensor is a touch sensor measuring contact force through resistance changes under deformation, the basis of force sensing resistors used in robotic skins and grasp control.

Resistivity logging

Resistivity logging is a well-logging technique that measures the electrical resistivity of rock formations around a borehole, used with Archie's equation to estimate porosity and water saturation in petroleum exploration.

Resistojet

A resistojet is an electrothermal spacecraft thruster in which an electrical resistance heater heats a gaseous propellant that expands through a nozzle, first flown on a US Navy satellite in 1965.

Resistor

A resistor is a passive two-terminal electronic component used in nearly every circuit; it opposes electric current, converting electrical energy into heat and creating a voltage drop per Ohm's law.