precessional


Also found in: Thesaurus, Medical, Encyclopedia.
Related to precessional: precesses

pre·ces·sion

 (prē-sĕsh′ən)
n.
1. The act or state of preceding; precedence.
2. Physics The motion of the axis of a spinning body, such as the wobble of a spinning top, when there is an external force acting on the axis.
3. Astronomy
a. Precession of the equinoxes.
b. A slow gyration of the earth's rotational axis around the pole of the ecliptic, caused by the gravitational pull of the sun, moon, and other planets on the earth's equatorial bulge.

[Late Latin praecessiō, praecessiōn-, from Latin praecessus, past participle of praecēdere, to go before; see precede.]

pre·ces′sion·al adj.
Mentioned in ?
References in classic literature ?
I thought of the great precessional cycle that the pole of the earth describes.
It's been measured with radio experiments on previous landers (one precessional cycle lasts about 166,000 years), but RISE's measurement will be more precise.
Today, STT is announcing a new breakthrough the company dubs Precessional Spin Current.
where [??] = [f.sub.1] sec 2[[omega].sub.0] and in particular, setting [f.sub.2] = [f.sub.1] = 0, we end up with a precessional motion with [alpha] = const., while [omega](t) and [[omega].sub.0](t) can still be determined from (84).
STIR relies on T1 relaxation differences instead of precessional frequency differences to cancel the signal from fat, thereby minimising susceptibility effects during fat-suppressed imaging.
When fat and water molecules occupy the same voxel, differences in precessional frequency quench MR signal in that voxel during opposed-phase gradient-echo MR imaging.
Ji, "Array ISAR of precessional cone target generated by intermittent sampling repeater jamming in fast and slow time," Journal of Electronics and Information Technology, vol.
Under the macrospin model and assuming a uniform ellipsoidal particle with demagnetizing tensor axes [N.sub.x], [N.sub.y], and [N.sub.z] ([N.sub.x] + [N.sub.y] + [N.sub.z] = 4[pi]), Kittel [13] derived the frequency for the uniform precessional mode, also known as ferromagnetic resonance mode as [[omega].sub.0] = [gamma][([[H.sub.z] + ([N.sub.y] - [N.sub.z])[M.sub.Z]] x [[H.sub.z] + ([N.sub.x] - [N.sub.z]) [M.sub.z]]).sup.1/2].
Sun, "Study on precessional motion simulation of ballistic missile midcourse," Applied Mechanics and Materials, vol.
For perfectly spherical source the lense thrilling precessional rates for the node and the perigee were obtained.
Let [[omega].sub.pcn] be the precessional angular speed, and let [v.sub.pcn] be the linear speed.