Technology and the built world

Harley-Davidson Super Glide

The Harley-Davidson Super Glide is a cruiser motorcycle introduced in 1971 as the FX Super Glide, credited as the industry's first factory custom, designed by Willie G. Davidson.

Harley-Davidson Touring, marketed as Grand American Touring, is a family of large long-distance motorcycles with hard saddlebags, fairings, and large-displacement V-twin engines, tracing to the 1965 Electra Glide.

Harley-Davidson Twin Cam engine

The Harley-Davidson Twin Cam is a 45-degree air-cooled pushrod V-twin that powered Big Twin motorcycles from 1999 to 2017, named for its two chain-driven camshafts, one per cylinder.

Harley-Davidson VRSC

The Harley-Davidson VRSC, marketed as the V-Rod, is a performance cruiser produced from 2002 to 2017, the first Harley-Davidson with overhead camshafts and liquid cooling.

Harllee Branch Generating Plant

Harllee Branch Generating Plant, known as Plant Branch, was a coal-fired power station in Putnam County, Georgia, owned by Georgia Power and retired between 2013 and 2015.

Harmaliyah Oil and Gas Field

Harmaliyah Oil and Gas Field (الحرملية) is an onshore oil field in Saudi Arabia's Eastern Province, discovered in 1971, operated by Saudi Aramco, and producing 35° API Arab-D oil.

Harman International

Harman International is an American audio and connected-car technology company headquartered in Stamford, Connecticut, and a wholly owned subsidiary of Samsung Electronics since 2017, owning audio brands including JBL, Harman Kardon, AKG, and Infinity.

Harman Kardon

Harman Kardon is an American audio brand founded in 1953 by Sidney Harman and Bernard Kardon, known for high-fidelity home audio, speakers, and premium car audio.

HarmBench

HarmBench is an open-source framework for automated red teaming of large language models, created by the Center for AI Safety and partners and published at ICML 2024.

Harmer E. Davis

Harmer E. Davis was an American civil engineer and UC Berkeley professor who directed the Institute of Transportation and Traffic Engineering from 1948 to 1973.

Harmon Trophy

The Harmon Trophy, or Harmon International Trophy, is a set of annual aviation awards founded by Clifford B. Harmon in 1926 for outstanding achievement in aeronautics.

Harmonic Drive

Harmonic Drive is a brand of strain wave gear, a compact, backlash-free speed reducer used in industrial and humanoid robots, invented by C. Walton Musser in 1957.

Harmonic filter

A harmonic filter is electrical equipment that reduces harmonic distortion in power systems by diverting or canceling harmonic currents from nonlinear loads such as variable frequency drives, rectifiers, and arc furnaces.

Harmonic mixer

A harmonic mixer is a frequency converter that mixes a harmonic of the local oscillator with an incoming radio frequency signal, chiefly used to down-convert millimeter-wave and terahertz signals.

Harmonic resonance

Harmonic resonance in power systems occurs when the system's natural frequency, set by inductance and capacitor banks, matches a harmonic source like a variable-frequency drive, amplifying harmonic voltages far above normal levels and damaging equipment.

Harmonic restraint

Harmonic restraint is a technique in transformer differential protection that uses the harmonic content of inrush current, especially the second harmonic, to prevent relay tripping.

Harmonics (electrical power)

Power system harmonics are voltage or current components at integer multiples of the 50 or 60 Hz fundamental, produced by non-linear loads and measured as total harmonic distortion (THD).

Harmonization of international emergency numbers

Harmonization of international emergency numbers is the effort to make codes like 112 and 911 work across national numbering plans, through ITU recommendations and EU mandates rather than a global registry.

Harmony Energy

Harmony Energy is a UK-headquartered developer and operator of grid-scale battery storage systems built on Tesla Megapacks, which Swiss energy company Alpiq acquired 90 per cent of in 2026.

Harmony Intelligent Mobility Alliance (鸿蒙智行)

Harmony Intelligent Mobility Alliance (鸿蒙智行, HIMA) is a Huawei-led automotive alliance in China, upgraded from the Huawei Zhixuan model in November 2023 and spanning five vehicle brands.

Harmony of the Seas

Harmony of the Seas is an Oasis-class cruise ship operated by Royal Caribbean International, built in Saint-Nazaire, France, and delivered in 2016 as the world's largest cruise ship.

Sep 29, 2026

Harmony search

Harmony search, also known as the harmony search algorithm, is a population-based metaheuristic optimization algorithm introduced in 2001, inspired by musical improvisation and applied to engineering design, scheduling, and machine learning tuning.

HarmonyOS

HarmonyOS, also known as HongMeng OS, is Huawei's operating system for phones, tablets, watches, cars, and other devices, launched in 2019 after US trade restrictions.

HarmonyOS 5

HarmonyOS 5, also known as HarmonyOS Next, is a mobile operating system developed by Huawei, launched in October 2024. It drops Android compatibility entirely, making it a third mobile operating system alongside Android and iOS.

Harness (company)

Harness is a San Francisco software company founded in 2017 by AppDynamics co-founder Jyoti Bansal, selling an AI-oriented software delivery platform for continuous integration, delivery, and security testing.

Harold A. Peterson

Harold A. Peterson was an American electrical engineer who spent twelve years at General Electric, then chaired the University of Wisconsin–Madison electrical engineering department for twenty years.

Harold A. Thomas

Harold A. Thomas Jr. was an American civil engineer and hydrologist at Harvard who led the Harvard Water Program and co-authored Design of Water-Resource Systems.

Harold Alden Wheeler

Harold Alden Wheeler (1903–1996) was an American radio-frequency engineer who invented automatic volume control, founded Wheeler Laboratories, held 180 patents, and won the 1964 IEEE Medal of Honor.

Harold B. Gotaas

Harold B. Gotaas (1906–1977) was an American sanitary engineer and professor at Berkeley and Northwestern whose research established composting fundamentals and sewage treatment by photosynthetic oxygen in open ponds.