-
1 wave stress
1) Морской термин: волновое напряжение2) Общая лексика: давление волны -
2 wave stress
Англо-русский словарь нефтегазовой промышленности > wave stress
-
3 wave stress
-
4 wave stress
-
5 significant wave stress
Морской термин: характерное волновое напряжениеУниверсальный англо-русский словарь > significant wave stress
-
6 significant wave stress
-
7 wave
- wave
- nволна
- air wave
- body wave
- compression wave
- explosion shock wave
- flood wave
- pressure wave
- pressure waves radiating outward from vibrator
- S wave
- shear wave
- shock wave
- stress wave
- translation wave
- wind wave
Англо-русский строительный словарь. — М.: Русский Язык. С.Н.Корчемкина, С.К.Кашкина, С.В.Курбатова. 1995.
-
8 wave
1) волна || волновой2) изменение; колебание3) сигнал•- cylindrical wave
- discontinuous stress wave
- echo waves
- longitudinal wave
- periodic wave
- plane wave
- profile wave
- progressive wave
- quadrature waves
- rectangular wave
- shock wave
- sine wave
- spherical wave
- square wave
- standing wave
- stress wave
- surface acoustic wave
- transverse wave
- ultrasonic wavesEnglish-Russian dictionary of mechanical engineering and automation > wave
-
9 stress
1) (механическое) напряжение; напряжённое состояние; условное напряжение2) нагрузка, усилие3) гидроудар4) воздействие5) нагрузка на единицу площади, интенсивность нагрузки, удельная нагрузка•- actual stress - admissible stress - advancing load stress - allowable stress - alternate stress - applied stress - arch stress - axial stress - bar stress - basic stress - bearing stress - belt stresses - bending stress - blow stress - bond stress - braking stress - breaking stress - calculated stress - chord stress - circular symmetrical stress - combined stress - completely reversed stresses - complex stress - compressive stress - compressive stress in bending - concrete stress - constant stress - cooling stress - couple stress - crack stress - crackforming stress - crippling stress - critical stress - critical compressive stress - cross-bending stress - cyclical stresses - dead stress - dead-load stress - design stress - direct stress - discontinuity stress - downward stress - dynamic stress - ecological stress - edge stress - effective stress - elastic stress - engineering stress - erection stress - external stress - fabrication stress - failing stress - fatigue stress - fatigue limit stress - fibre stress - final stress - flexural stress - floor stress - fluctuating stresses - friction-induced stress - functional stress - gravity stress - ground stress - handling stress - heat stress - hoist stresses - hoop stress - horizontal stress - impact stress - indirect stress - induced stress - inherent stresses - initial stress - intermediate stress - internal stress - jacking stress - lateral stress - limiting maximum stress - linear stress - live load stress - load stress - local stresses - locked-up stresses - longitudinal stress - mechanical stress - net stress - neutral stress - normal stress - operating stress - operational stress - permissible stress - plane stress - point-load stress - primary stress - principal stresses - proof stress - radial stress - reinforcement stresses - relaxation of stresses - repeated stresses - residual stress - reverse stress - rupture stress - safe stress - secondary stress - shearing stress - shock stress - simple stress - snow load stress - specific stress - static stress - subsidiary stress - surface stress - sustained stress - sway stress - tangential stress - temperature stress - tensile stress - thermal stress - thermal stress on structure - three-dimensional stress - time-dependant stress - torsional stress - total stress - transverse stress - true stress - twisting stress - ultimate stress - uniaxial stress - unit stress - unsafe stress - varying stress - vibratory stress - volumetric stress - water stress - wave stress - welding stress - wheel-load stress - wind stress - working stress - yield stress - yield point stressstress due to prestress — усилие ( в бетоне), вызванное предварительным напряжением
* * *1. (внутреннее) усилие, внутренняя сила2. (механическое) напряжение3. нагрузка на единицу площади, интенсивность нагрузки, удельная нагрузкаstress acting away from the joint — усилие ( в элементе фермы), действующее от узла
stresses arising from bending and axial loading — напряжения, возникающие от поперечного изгиба и действия продольных сил
stress constant across the section — напряжение, постоянное по всему сечению
stress due to prestress — усилие обжатия бетона; напряжение в бетоне, вызванное обжатием
stresses due to wind forces — напряжения от сил ветра, напряжения от ветровой нагрузки
stresses induced by loads — напряжения, вызванные нагрузкой [нагружением] ( в отличие от температурных напряжений)
stress in reinforcement — напряжение [усилие] в арматуре
stresses in truss components [in truss members] — усилия в стержнях [элементах фермы]
stress resolved into two components — напряжение, разложенное на две составляющие
stress varying from point to point — напряжение, меняющееся от точки к точке ( сечения элемента)
- actual stressstresses with the elastic limit — напряжения, не превышающие предела упругости; напряжения в упругой области
- additional stress
- allowable stress
- allowable unit stress
- alternate stress
- anchorage bond stress
- average stress
- axial stress
- bar stress
- bearing unit stress
- bearing stress
- belt stress
- bending stress
- bending failure stress
- biaxial stress
- blow stress
- bond stress
- bottom-chord stress
- boundary stress
- breaking stress
- buckling stress
- calculated stress
- circumferential unit stress
- circumferential stress
- combined stresses
- combined bearing, bending, and shear stresses
- combined shear and bending stress
- compression stress
- compressive stress in bending
- concentrated-load stress
- constant stress
- crack-inducing stress
- crippling stress
- critical stress
- crushing stress
- cycle stress
- dead load stress
- design stress
- development bond stress
- deviation stress
- deviator stress
- direct stress
- drying shrinkage stresses
- dynamic stress
- edge stress
- effective stress
- equivalent stress
- erection stress
- extreme fiber stress
- extreme stress
- failure stress
- fatigue stress
- fiber stress
- final stress
- flexible stress
- floor stress during operation
- floor stress when climbing
- flow stress
- fluctuating stresses
- fracture stress
- freezing stresses
- gravity stress
- handling stresses
- high localized stresses
- hoop stress
- hydrostatic stress
- ideal main stress
- impact stresses
- initial stresses
- intergranular stress
- intermediate principal stress
- jacking stress
- larger principal stress
- limiting stresses permitted in the standard
- linearly varying stresses
- live-load stress
- local stresses
- local bond stress
- longitudinal stress
- main stress
- maximum stress
- maximum allowable stress
- maximum shearing stress
- mean stress
- mean cycle stress
- mean fatigue stress
- membrane stresses
- meridian stress
- negative normal stress
- neutral stress
- normal stress
- octahedral normal stress
- octahedral shear stress
- peak stress
- permissible stress
- plate stresses
- point-load stress
- positive normal stress
- primary stress
- principal stresses
- principal tensile stress
- proof stress
- proof stress at 0.2 percent set
- pulsating stress
- radial stress
- radial shearing stress
- reduced main stress
- reinforcement stress
- repeated stress
- residual stress
- reversed stress
- rupture stress
- safe stress
- secondary stresses
- service stress
- settlement stresses
- shear stress
- shear stresses on oblique planes
- shear buckling stress
- shearing stress
- shrinkage-related stress
- shrinkage stress
- smaller principal stress
- spherical stress
- splitting tensile stress
- static stress
- surface stress
- tangential stress
- temperature stress
- temporary stress
- tensile stress
- tensile stress due to bending
- thermal stress
- timber stresses
- time-dependent stress
- top-chord stress
- torsional stress
- total stress
- transverse bending stress in flange
- true stress
- truss stresses
- truss stresses determined by method of sections
- twisting stress
- ultimate stress
- ultimate shear stress
- ultimate tensile stress
- unit stress
- unit stress produced by design loads
- unrelieved stress
- working stress
- yield stress -
10 wave
1) волна2) колебание; (колебательный) сигнал3) графическое изображение колебательного процесса•-
abrupt translatory wave
-
acceleration wave
-
acoustic surface wave
-
acoustic wave
-
advancing wave
-
Alfven wave
-
arriving wave
-
atmospheric wave
-
back wave
-
background wave
-
backscattered wave
-
backward wave
-
bed wave
-
blast wave
-
Bloch wave
-
body wave
-
bottom wave
-
buckle wave
-
bulk acoustic wave
-
capillary wave
-
carrier wave
-
chopped wave
-
circularly polarized wave
-
clockwise-polarized wave
-
coincident wave
-
cold wave
-
complex wave
-
compressional wave
-
compression wave
-
confined wave
-
conical wave
-
conjunctional wave
-
continuous wave
-
convergent waves
-
converted wave
-
cosine wave
-
counterclockwise-polarized wave
-
creeping wave
-
critical wave
-
cross wave
-
current wave
-
damped wave
-
de Broglie waves
-
decadent wave
-
degenerative wave
-
density wave
-
detonation wave
-
diagonal sea wave
-
diffracted wave
-
dilatational wave
-
direct shock wave
-
direct wave
-
disturbance wave
-
disturbed wave
-
disturbing wave
-
diving wave
-
dynamic waves
-
E wave
-
earthquake wave
-
elastic wave
-
electric wave
-
electromagnetic wave
-
elliptically polarized wave
-
emitted wave
-
evanescent wave
-
extraneous wave
-
extraordinary wave
-
flexural wave
-
forming wave
-
forward wave
-
forward-scattered wave
-
forward-traveling wave
-
free-progressive wave
-
free-space wave
-
frontal wave
-
full wave
-
fundamental wave
-
gravity wave
-
ground wave
-
ground-reflected wave
-
growing wave
-
guided wave
-
harmonic wave
-
head wave
-
heat wave
-
hectometric waves
-
Hertzian waves
-
Hertz waves
-
homogeneous wave
-
horizontally polarized wave
-
H-wave
-
hybrid electromagnetic wave
-
hydraulic-jump wave
-
hydrodynamic wave
-
illuminating wave
-
image wave
-
impinging wave
-
incoming wave
-
indirect wave
-
inhomogeneous wave
-
interacting waves
-
interface wave
-
interfacial waves
-
ionospheric wave
-
kilometric waves
-
knock wave
-
leaky wave
-
left-handed polarized wave
-
light wave
-
linearly polarized wave
-
long waves
-
longitudinal wave
-
Love wave
-
magnetic wave
-
magnetoacoustic wave
-
magnetohydrodynamic wave
-
magnetostatic wave
-
magnon wave
-
maintained wave
-
meander wave
-
medium waves
-
Mintrop wave
-
modulated continuous wave
-
modulated wave
-
negative release wave
-
neutron wave
-
nonhomogeneous wave
-
nonpolarized wave
-
object wave
-
oblique shock wave
-
oblique wave
-
optical wave
-
ordinary wave
-
orthogonally polarized wave
-
outsized waves
-
passing ship wave
-
periodic wave
-
phonon wave
-
plane harmonic horizontally polarized shear wave
-
plane wave
-
plane-polarized wave
-
plastic wave
-
polarized wave
-
positive release wave
-
pressure wave
-
primary tide wave
-
progressive wave
-
radiated wave
-
radio wave
-
rarefaction wave
-
Rayleigh wave
-
reconstructing wave
-
recording wave
-
reference wave
-
reflected wave
-
refracted wave
-
release wave
-
return wave
-
reverse-traveling wave
-
right-handed polarized wave
-
ripple wave
-
roll wave
-
rotational wave
-
running wave
-
sawtooth wave
-
scattered wave
-
seismic sea wave
-
Shallamach waves
-
shear wave
-
ship-induced wave
-
ship wave
-
shock wave
-
short waves
-
shrinking wave
-
SH-wave
-
sine wave
-
sky wave
-
solitary wave
-
sonic wave
-
spacing wave
-
spherical wave
-
spin wave
-
square wave
-
standing wave
-
stationary wave
-
stem wave
-
stray wave
-
stress wave
-
suction wave
-
surface acoustic wave
-
surface wave
-
SV-wave
-
S-wave
-
temperature wave
-
torsional wave
-
transmitted wave
-
transverse electric wave
-
transverse magnetic wave
-
transverse wave
-
traveling wave
-
tropospheric wave
-
tube wave
-
twin wave
-
ultrashort waves
-
ultrasonic waves
-
undamped wave
-
undistorted wave
-
upper tropospheric waves
-
vertically polarized shear wave
-
vertically polarized wave
-
volume acoustic wave
-
water-hammer wave
-
wave of water table
-
wind-induced wave
-
wind wave -
11 wave
1) волна
2) взмах
3) волновой
4) махать
5) <commun.> сигнал
6) волноваться
7) развеваться
8) колебательный
9) колебание
– acoustic wave
– air wave
– backward wave
– beam wave
– blast wave
– boundary wave
– bow shock wave
– bow wave
– bulk-surface wave
– carrier wave
– catcher wave
– coherent wave
– compression wave
– conducting a wave
– creeping wave
– current wave
– density wave
– depression wave
– detonation wave
– diffracted wave
– direct wave
– edge wave
– EH wave
– elastic wave
– evanescent wave
– extraordinary wave
– flexural wave
– free-space wave
– fundamental wave
– gap wave
– gravity wave
– ground wave
– ground-reflected wave
– guided wave
– half wave
– harmonic wave
– helicon wave
– HF wave band
– idler wave
– incident wave
– ingoing wave
– inhomogeneous wave
– interferential wave
– ionospheric wave
– lateral wave
– longitudinal wave
– Mach wave
– magnon wave
– marking wave
– micro wave
– modulated wave
– node of wave
– ordinary wave
– orthogonal wave
– overdriven wave
– partial wave
– pertaining to wave
– pilot wave
– plane wave
– plane-polarized wave
– plasma wave
– polarized wave
– polarographic wave
– primary wave
– reference wave
– reflected wave
– return wave
– saw-tooth wave
– scattered wave
– shear wave
– shock wave
– short wave
– side wave
– sine wave
– sky wave
– slot wave
– space wave
– spherical wave
– square wave
– standing wave
– stationary wave
– stress wave
– surface wave
– tenth wave
– transient wave
– transverse wave
– travelling wave
– undistorted wave
– unguided wave
– VHF wave band
– wave acoustics
– wave analyzer
– wave band
– wave conductor
– wave crest
– wave dispersion
– wave distance
– wave disturbance
– wave duct
– wave equation
– wave filter
– wave frequency
– wave front
– wave function
– wave guide
– wave height
– wave impedance
– wave interference
– wave mechanics
– wave mode
– wave number
– wave of probability
– wave operator
– wave optics
– wave packet
– wave pattern
– wave propagation
– wave range
– wave refraction
– wave resistance
– wave rule
– wave shape
– wave steepness
– wave tilt
– wave train
– wave trough
– wave velocity
– whistler wave
continuous wave laser — лазер непрерывного излучения, лазер непрерывного режима работы
elliptically polarized wave — эллиптически волна поляризованная
long-range wave propagation — дальнее распространение радиоволн
oblique shock wave — <phys.> скачок уплотнения косой
pregressing shock wave — <acoust.> волна ударная автомодельная
reflected wave method — < radio> метод отраженных волн
square wave generator — <tech.> генератор прямоугольных сигналов
surface wave line — < radio> линия поверхностной волны
surface-skimming bulk wave — волна объемная приповерхностная
transverse compressional wave — <geogr.> волна поперечная упругая
transverse electric wave — < radio> волна поперечная электрическая
transverse electromagnetic wave — < radio> волна поперечная электромагнитная
transverse magnetic wave — < radio> волна поперечная магнитная
traveling wave antenna — < radio> антенна бегущей волны
uniform-phase wave front — волновой фронт с постоянной фазой
vertically polarized wave — вертикально поляризованная волна
wave drag coefficient — <phys.> коэффициент волнового сопротивления
-
12 wave
1) волна; струя2) колебание3) неровность; ухаб дороги•- air shock wave - atmospheric tidal wave - audio-frequency wave - blanking wave - blast wave - body wave - bottom wave - bow wave - breaking wave - capillary wave - carrier wave - centimetre waves - cold wave - compressible shock wave - compression wave - condensational wave - constant wave - continuous wave - convergent shock wave - damped waves - decadent wave - decaying wave - deep-water wave - deflection wave - density wave - detached shock wave - detonation wave - direct wave - earth wave - elastic wave - electromagnetic wave - expansion wave - expansion shock wave - explosion shock wave - explosive wave - flood wave - free wave - free progressive wave - frequency-modulated wave - fundamental wave - harmonic wave - heat wave - Hertz waves - hydraulic jump wave - infrared waves - infrasonic waves - inhomogeneous wave - intensity wave - interrupted wave - inverse wave - knock wave - lunar tidal wave - magnetoacoustical wave - modulated continuous wave - moving wave - normal shock wave - oblique shock wave - operating wave - oscillatory wave - positive pressure wave - power wave - pressure wave - progressive wave - radio waves - rarefaction wave - reflected wave - resonance wave - return wave - running wave - seismic waves - shock wave - signal wave - sound wave - stable wave - standing wave - subsurface wave - suction wave - supersonic waves - surface wave - tension wave - tidal wave - torsional wave - trailing wave - travelling wave - ultrasonic waves - vertical wave - water-hammer wave* * *волна- air wave
- body wave
- compression wave
- explosion shock wave
- flood wave
- pressure wave
- pressure waves radiating outward from vibrator
- S wave
- shear wave
- shock wave
- stress wave
- translation wave
- wind wave -
13 wave
1) волна || волновой2) колебание || колебательный3) связь сигнал4) взмах || махать5) развеваться6) волноваться ( о море)•- air wave- atmospheric radio wave- bow wave- gap wave- sky wave- surface-skimming bulk wave - transverse compressional wave - transverse electromagnetic wave -
14 wave
Alpha wavesattached shock wavebending waveBeta wavesbow wavebrain wavescompression wavecreeping wavecylindrical wavedeflection waveDelta wavedetached shock waveelastic waveelectromagnetic waveexpansion waveflexural waveimpinging waveincident waveleading-edge shock waveMach wavemoderate shock wavemountain wavesnormal shock waveoblique waveoblique shock waveoutgoing waveplane wavepressure waveRayleigh wavereactive shock wavescattered waveshear waveshock wavesine waveskewed shock wavesolitary wavestanding wavestress wavestrong shock wavesurface wavetensile waveTollmien-Schlichting wavestorsional wavetrailing edge shock wavetravelling wavewing shock wave -
15 stress wave
- stress wave
- n
Англо-русский строительный словарь. — М.: Русский Язык. С.Н.Корчемкина, С.К.Кашкина, С.В.Курбатова. 1995.
-
16 stress wave
-
17 stress wave
English-German dictionary of Electrical Engineering and Electronics > stress wave
-
18 stress
1) (механическое) напряжение || вызывать напряжение, напрягать3) нагрузка; усилие4) воздействие•to induce stress — вызывать напряжение, напрягать;to remove stress — устранять [снимать\] напряжение;to take stress — воспринимать напряжение-
actual stress
-
allowable stress
-
alternate stress
-
axial stress
-
bearing stress
-
bending stress
-
biaxial stress
-
breakdown voltage stress
-
breaking stress
-
buckling stress
-
bursting stress
-
cleavage stress
-
combined stress
-
complex stress
-
composite stress
-
compound stress
-
compressional stress
-
compression stress
-
compressive stress
-
couple stress
-
crack tip stress
-
crippling stress
-
cyclic stresses
-
design stress
-
dielectric stress
-
direct stress
-
dislocation locking stress
-
docking stresses
-
drag stress
-
dynamic stress
-
dynamic yield stress
-
ecological stress
-
edge stress
-
effective stress
-
elastic stress
-
elastic-plastic stress
-
electric stress
-
electrostrictive stress
-
engineering stress
-
environmental stress
-
erection stress
-
Euler crippling stress
-
failing stress
-
fiber stress
-
final stress
-
flexural stress
-
flow stress
-
fluctuating stress
-
fracture arrest stress
-
functional stress
-
heat stress
-
hogging stresses
-
homogeneous stress
-
hoop stress
-
horizontal stress
-
hull girder stresses
-
impact stress
-
inception voltage stress
-
induced stress
-
inherent stress
-
initial stress
-
instantaneous stress
-
interfacial shear stress
-
internal stress
-
jacking stress
-
limit stress
-
linear stress
-
local stress
-
longitudinal stress
-
magnetostrictive stress
-
net stress
-
normal stress
-
notch stress
-
operating voltage stress
-
permissible stress
-
plane stress
-
potential stress
-
principal stress
-
proof stress
-
remote stress
-
residual stress
-
reversed stress
-
Reynolds stress
-
safe stress
-
sagging stresses
-
shearing stress
-
shear stress
-
shrinkage stress
-
simple stress
-
slamming stresses
-
springing stresses
-
static stress
-
still-water stresses
-
strata stress
-
sustained stress
-
tangential stress
-
tectonic stresses
-
temperature stress
-
tensile stress
-
thickness stress
-
three-dimensional stress
-
torsional stress
-
triaxial stress
-
turbulent stress
-
twisting stress
-
two-dimensional stress
-
ultimate stress
-
uniaxial stress
-
unit stress
-
voltage stress
-
volumetric stress
-
water stress
-
wave-induced stresses
-
wave stresses
-
wind stress
-
working stress
-
working voltage stress
-
yield stress -
19 stress
1) напрягать
2) напряжение
3) тяжение
4) давление
5) напряженный
6) усилие
– alternate stress
– bending stress
– bond stress
– braking stress
– breaking stress
– cleavage stress
– combined stress
– compressive stress
– cooling stress
– design stress
– distribute a stress
– elastic stress
– fatigue stress
– generate a stress
– heat stress
– hogging stress
– hoop stress
– hoopential stress
– impact stress
– internal stress
– linear stress
– load stress
– membrane stress
– principal stress
– relieve a stress
– residual stress
– reversal of stress
– rupture stress
– safe stress
– sagging stress
– secondary stress
– shear stress
– shearing stress
– shrinkage stress
– simple stress
– specific stress
– stress analysis
– stress arises
– stress concentration
– stress corrosion
– stress detector
– stress deviator
– stress ellipsoid
– stress freezing
– stress loading
– stress steel
– stress surface
– stress tensor
– stress test
– stress wave
– surface stress
– tangential stress
– temperature stress
– tensile stress
– thermal stress
– torsional stress
– true stress
– ultimate stress
– unit stress
– viscous stress
– volumetric stress
– yield stress
-
20 wave
См. также в других словарях:
Wave equation analysis — is a numerical method of analysis for the behavior of driven foundation piles. It predicts the pile capacity versus blow count relationship (bearing graph) and pile driving stress. The model mathematically represents the pile driving hammer and… … Wikipedia
Wave Dragon — is a floating slack moored energy converter of the overtopping type, located in the northern Denmark. It was the world s first offshore wave energy converter. Wave Dragon is a joint EU research project, including partners from Austria, Denmark,… … Wikipedia
stress portfolio — (STRES port.foh.lee.oh) n. The collection of events and situations that cause stress in a person s life. Example Citation: Thanks to economic turmoil abroad, gyrating U.S. markets and stepped up corporate retrenchment, a new wave of job angst is… … New words
stress wave — įtempio banga statusas T sritis fizika atitikmenys: angl. stress wave vok. Spannungswelle, f rus. волна напряжения, f pranc. onde de contrainte, f … Fizikos terminų žodynas
Wave Motion (album) — Infobox Album | Name = Wave Motion Type = Album Artist = Fat Jon Released = October 22, 2002 Genre = Hip Hop Label = Mush Producer = Fat Jon Reviews = *Allmusic Rating|4.5|5 [http://allmusic.com/cg/amg.dll?p=amg sql=10:5gq8g4sptv2z Link]… … Wikipedia
Wave-piercing — A wave piercing boat hull has a very fine bow, with reduced buoyancy in the forward portions.When a wave is encountered, the lack of buoyancy means the hull pierces through the water rather than riding over the top resulting in a smoother ride… … Wikipedia
Heat wave — A heat wave is a prolonged period of excessively hot weather, which may be accompanied by high humidity. There is no universal definition of a heat wave;cite journal |last=Meehl |first=George A. |coauthors=Tebaldi, Claudia |title=More Intense,… … Wikipedia
Airy wave theory — In fluid dynamics, Airy wave theory (often referred to as linear wave theory) gives a linearised description of the propagation of gravity waves on the surface of a homogeneous fluid layer. The theory assumes that the fluid layer has a uniform… … Wikipedia
Kelvin wave — A Kelvin wave is a wave in the ocean or atmosphere that balances the Earth s Coriolis force against a topographic boundary such as a coastline. A feature of a Kelvin wave is that it is non dispersive, i.e., the phase speed of the wave crests is… … Wikipedia
Gravitational wave — In physics, a gravitational wave is a fluctuation in the curvature of spacetime which propagates as a wave, traveling outward from a moving object or system of objects. Gravitational radiation is the energy transported by these waves. Important… … Wikipedia
T wave alternans — (TWA) is a periodic beat to beat variation in the amplitude or shape of the T wave in an electrocardiogram (ECG or EKG). T wave of ECG TWA was first described in 1908. At that time, only large variations ( macroscopic TWA) could be detected.… … Wikipedia