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Related to precessional: precesses


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.
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I thought of the great precessional cycle that the pole of the earth describes.
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.
His tales are filled with haunting astronomical images--a waning crescent moon casting its feeble light on moldering gravestones; frosty Aldebaran seeming to balance on a steeple over an ancient, worm-bedeviled Massachusetts seaport; Polaris, steeped in prehistoric secrets from its 26,000-year precessional cycle, "winking hideously like an insane watching eye.
So, it is important to build the wideband radar echo model of midcourse precessional target.
From the perspective of the precessing magnetic moments, the biomagnetic field generated by neuronal activity also contributes to the applied magnetic field, thereby altering their precessional frequencies.
The best studied is 56 Ari [10] whose magnetic axis has a precessional period of 5 years.
The importance of precessional signals in the tropical climate.
However, all orbital cycles, including the 19 000 to 23 000-year precessional cycle, were operative regardless of which climatic conditions dominated and what soil developed (Rutter et al.