All articles A–Z

Soft story

A soft story is a building story, often an open ground floor, whose lateral stiffness is much lower than the stories above it, making it vulnerable in earthquakes.

Soft supersymmetry breaking is a way of breaking supersymmetry by adding restricted terms to the Lagrangian that keep its good renormalization properties, especially quadratic-divergence cancellation.

Soft switching

Soft switching is a power electronics technique that turns transistors on or off at zero voltage (ZVS) or zero current (ZCS) via resonance, reducing switching losses and electromagnetic interference compared with hard switching.

Soft systems methodology

Soft systems methodology (SSM) is an action-oriented inquiry process for messy problem situations, developed by Peter Checkland at Lancaster University and matured in his 1981 book Systems Thinking, Systems Practice.

Soft tennis at the 2026 Asian Games

Soft tennis at the 2026 Asian Games (ソフトテニス): five-event discipline at the Aichi-Nagoya Games, September 18–23, 2026, at Nagoya City Higashiyama Park Tennis Center; South Korea won 3 bronzes and no gold for the first time in 32 years.

Soft theorems

Soft theorems are universal statements about scattering amplitudes when an emitted photon, gluon, or graviton carries vanishing energy, first derived by Steven Weinberg in 1965 and greatly expanded after 2014.

Soft tissue biopsy

A soft tissue biopsy is a diagnostic procedure that removes a sample of muscle, fat, or connective tissue for microscopic examination to identify disease, especially tumors.

Soft tissue therapy

Soft tissue therapy is a family of hands-on and instrument-assisted treatments targeting muscles, tendons, ligaments, and fascia, including massage, myofascial release, Rolfing, trigger point release, and IASTM.

Oct 20, 2026

SOFT trial

SOFT (Suppression of Ovarian Function Trial), IBCSG phase III trial NCT00066690 in 3,047 premenopausal women with hormone receptor-positive early breast cancer, testing 5 years of tamoxifen, tamoxifen+ovarian suppression, or exemestane+ovarian suppression; benefit concentrated in higher-risk and under-35 patients.

Soft underwater robot

A soft underwater robot is an aquatic robot built from compliant materials like silicone, inspired by octopuses and fish for gentle reef observation and sampling.

Soft X-ray

A soft X-ray is a lower-energy, longer-wavelength X-ray, spanning the water window near 2.3 to 4.4 nm, used to image intact cells and probe materials.

Oct 22, 2026

Soft X-ray laser

A soft X-ray laser is a laser emitting coherent radiation in the soft X-ray region, produced in highly ionized plasmas, either as compact tabletop systems or large free-electron facilities.

Oct 22, 2026

Soft X-ray magnetic laminography

Soft X-ray magnetic laminography is a 3D imaging technique that reconstructs magnetization in thin magnetic samples from XMCD projections, first demonstrated at the Swiss Light Source in 2020.

Soft X-ray scattering

Soft X-ray scattering is an X-ray technique using photons around 200 to 2000 eV to probe electronic structure, magnetism, and nanoscale order, with element- and valence-specific contrast.

Soft x-ray tomography

Soft x-ray tomography is an imaging method that reconstructs a 3D map of a specimen's x-ray absorption, used mainly for quantitative imaging of whole, unstained cryo-preserved cells.

Soft-coated Wheaten Terrier

Soft-coated Wheaten Terrier, an Irish farm terrier breed with a soft, silky wheaten single coat; recognized by the Irish KC in 1937 and AKC in 1973; dogs 18–19 inches, 35–40 pounds; UK median survival 13.7 years; prone to familial PLE/PLN.

Soft-collinear effective theory

Soft-collinear effective theory (SCET) is an effective field theory of quantum chromodynamics describing processes with energetic jets and soft radiation, expanding amplitudes in the small ratio Λ/Q.

Soft-core processor implementation on FPGAs

A soft-core processor is a CPU described in a hardware description language and synthesized onto an FPGA's generic logic fabric, offering portability and lower cost than fixed silicon cores.

Soft-decision decoding

Soft-decision decoding is a family of error-correction methods that pass each received symbol's reliability to the decoder, gaining roughly 1.5 to 2.3 dB over hard decisions.

Soft-decision FEC

Soft-decision FEC (SD-FEC) is forward error correction that decodes using multi-level, confidence-bearing receiver output, typically using LDPC or turbo product codes for about 3 dB more gain than hard-decision codes.

Soft-input soft-output

Soft-input soft-output (SISO) is a decoder design that passes reliability information, usually log-likelihood ratios, between receiver components so iterative schemes like turbo decoding can converge, using algorithms such as the BCJR of 1974.

Soft-output MIMO detection

Soft-output MIMO detection is a receiver component that separates spatially multiplexed MIMO data streams and computes a log-likelihood ratio for each coded bit for the channel decoder.

Soft-output Viterbi algorithm

The soft-output Viterbi algorithm (SOVA) is a variant of the Viterbi algorithm that also gives a reliability value for each decoded symbol, introduced by Hagenauer and Hoeher in 1989.

Soft-point bullet

Soft-point bullet: jacketed rifle or pistol projectile with exposed lead tip that mushrooms on impact; variants RSP, PSP, JSP; Hague 1899, hunting use.

Soft-shell crab

Soft-shell crab is a crab eaten just after molting, before its new shell hardens; not a species. Centered on Chesapeake Bay blue crab (Callinectes sapidus) and Asian farmed Scylla mud crabs, produced in shedding floats and tanks.

Softail

Softail is a family of Harley-Davidson cruiser motorcycles with a hidden rear shock that preserves the vintage hard tail look, introduced in 1984 and still the basis of the company's Cruiser lineup.

Softball

Softball: bat-and-ball sport invented 1887 at Chicago's Farragut Boat Club by George Hancock; renamed softball in 1926; seven-inning WBSC rules; Olympic women's event since 1996.

Softball at the 2020 Summer Olympics

Softball at the 2020 Summer Olympics: women's tournament, 21-27 July 2021, Yokohama and Fukushima. Japan beat USA 2-0 for a second straight gold; Canada took bronze; six teams competed.

Softball at the 2026 Asian Games

Softball at the 2026 Asian Games: women's softball at the 20th Asian Games in Anjo, Aichi, Japan, 26 September to 3 October 2026. Eight teams; Japan beat China 7-0 for gold, its seventh straight title; Chinese Taipei took bronze.