2. To abstain from applying or enforcing a rule, a restriction, or a fee: "The college will waive Mary's tuition expenses because she has a scholarship that will pay for the necessary costs."
"The schools waive the costs for books for low-income students."
2. A strong feeling that suddenly affects someone: "An unexpected wave of fatigue overcame Robin after working two days without sleep."
With the wave of her pen, the librarian was able to waive the overdue fine on the book which Frank lost and he was happy to wave goodbye as a sign of appreciation.
2. The normal brainwave in the electroencephalogram of a person who is awake but relaxed.
3. A pattern of smooth, regular electrical oscillations in the human brain that occur when a person is awake and relaxed.
As recorded by the electroencephalograph, alpha waves have a frequency of 8 to 13 hertz.
In alpha biofeedback training, the subject receives information on his or her EEG as a means of achieving a state of relaxation.
In one technique, a tone sounds in the absence of alpha waves and disappears when the subject produces alpha waves.
2. In electroencephalography, a rapid rhythm usually of low voltage, which can be recorded in the motor areas of the brain and sometimes in the frontal regions; especially, during states of stress or anxiety or after the administration of certain drugs such as barbiturates.
3. The second most common waveform occurring in electroencephalograms of the adult brain, characteristically having a frequency from 13 to 30 cycles per second.
It is associated with an alert waking state but can also occur as a sign of anxiety or apprehension.
2. A zone of burning propagated or transmitted through a combustible medium.
3. The zoned, reacting, gaseous material formed when an explosive mixture is ignited.
2. A network that transmits alternating currents of desired frequencies while substantially attenuating all other frequencies.
A transverse electric wave and a transverse magnetic wave are electromagnetic waves in which the magnetic field vectors are every where perpendicular to the directions of propagation.
2. An electromagnetic wave of significant intensity that results when waves with different intensities propagate with different velocities in a nonlinear optical medium, and faster-traveling waves from a pulse of light catch up with preceding, slower traveling waves.
2. A wave which consists of both electric and magnetic variation.
3. A wave of electromagnetic radiation generated by the oscillation of a charged particle and characterized by periodic variations of electric and magnetic fields.
4. A wave of energy made up of an electric and a magnetic field which is generated when an electric charge oscillates or is accelerated.
Light waves and radio waves are electromagnetic waves, according to their frequencies and wavelengths.
The primary kinds of electromagnetic waves, ranging from the longest to the shortest wave length, are long radio waves, short radio waves, infrared rays, visible light, ultraviolet light, X-rays, and gamma rays.
2. Any device to transmit electromagnetic waves of desired frequencies while substantially reducing the strength of all of the other frequencies.
2. A wave in a plasma that moves parallel to the magnetic field produced by currents outside the plasma at frequencies less than that of the electron cyclotron resonance, and which is circularly polarized, rotating in the same sense as electrons in the plasma; responsible for whistlers.
A whistler is defined as an effect that occurs when a plasma disturbance, caused by a lightning discharge, travels out along lines of magnetic force of the earth's field and is reflected back to its origin from a magnetic point on the earth's surface.
The square of the function's modulus gives the probability per unit volume of finding electrons at a given position.
2. An electron tube in which stream of electrons having different velocities interact and cause a progressive change in signal modulation along their length.
2. A radio wave that travels upward into space and may or may not be returned to earth by reflection from the ionosphere.
3. A radio wave that is transmitted around the curved surface of the earth by being reflected back to earth by the ionosphere.
Waves of Destruction
Earthquakes are said to radiate destruction much like bomb blasts in that seismic waves burst from the underground hypocenter (the point within the earth where an earthquake rupture starts; also known as the focus).
Surface waves consist of heaving waves produced by P and S waves. The P wave is the fastest wave which is generated by the fault rupture and it compresses and stretches the rock area. The S wave is slower but often the more destructive wave as it shakes rock from side to side.
- P waves, which compress and stretch rock, deliver the quake's initial thrust.
- Slower and often more destructive S waves follow, slithering side to side.
- S waves tear buildings off foundations and can churn wet soils into a mixture that acts like quicksand, causing buildings to tilt.
- At ground level, P and S waves produce surface waves that can flatten bridges, crack windows, or simply pass unnoticed.
- Eventually the waves weaken as they roll away from the hypocenter; but the seismic echoes of powerful quakes can resonate across and around the globe
A "Rayleigh wave" is a seismic surface wave causing the ground to shake in an elliptical motion, with no transverse, or perpendicular, motion.
A "Love wave" is a surface wave having a horizontal motion that is transverse (or perpendicular) to the direction the wave is traveling.
Typical seismic sources; such as, vibrators and air-gun arrays emit elastic waves that are assumed to be spherical waves.
Variations in the reflected signal can be used to provide a unique identity.
It occurs naturally in children up to about 12 years of age, but it is considered abnormal in adults.2. The normal brainwave in the encephalogram of a person who is awake but relaxed and drowsy.
It occurs with low frequency and low amplitude.3. A relatively high amplitude brain wave pattern between approximately 4 and 9 hertz that is characteristic; especially, of the hippocampus but occurs in many regions of the brain including the cortex.
Supposing that such a wave could be set up in the first place, the theory suggests that the spiral arms mark the positions of regions of higher than average density, which rotate around the galaxy.
Stars orbiting the center of the galaxy spend a considerable amount of time in the higher density regions before moving out, with the higher density also favoring the formation of young stars by fragmentation within it.
It has less harmonic content than a square wave.