| 释义 |
oscillate, v.|ˈɒsɪleɪt|
[f. L. oscillāt-, ppl. stem of oscillāre to swing: see -ate3.]
1. a. intr. To swing backwards and forwards, like a pendulum; to vibrate; to move to and fro between two points.
1726Stone Math. Dict. s.v. Oscillation, If a single Pendulum be suspended between two Semi-Cycloids..so that the String as it oscillates, folds about them, all the Oscillations, however unequal, will be Isochronal in a Non-resisting Medium. 1756Burke Subl. & B. iv. xii, Move any body, as a pendulum, in one way, and it will continue to oscillate in an arch of the same circle, until the known causes make it rest. 1802Playfair Illustr. Hutton. Th. 438 There is a certain mean condition, about which our system perpetually oscillates. 1840Carlyle Heroes iv. (1872) 127 You look at the waves oscillating hither, thither on the beach. 1869Phillips Vesuv. iv. 110 The magnetic needles oscillated both vertically and horizontally.
b. loosely. To move or travel to and fro.
1865Dickens Mut. Fr. iii. iv, Miss Lavinia, oscillating between the kitchen and the opposite room, prepared the dining-table in the latter chamber. 1891N. Gould Double Event 316 He spends his time oscillating between Australia and England and vice-versâ.
c. Electronics. Of a circuit or device: to cause oscillations in an electric current flowing in it.
1917R. D. Bangay Elem. Princ. Wireless Telegr. I. 84 The methods employed for causing an aerial to oscillate, and thus radiate electric waves, fall under two headings. 1928Times 23 Mar. 20/1 If too much retroaction is employed the circuit resistance may become negative, when the whole system will begin to oscillate. 1948A. L. Albert Radio Fund. x. 370 If some of the output signal voltage is fed back into the control-grid in the proper manner, a vacuum tube will oscillate. 1971L. T. Agger Introd. Electr. xxiv. 432 A circuit containing inductance and capacitance will oscillate at its own natural frequency, provided it is left undisturbed after the oscillation has been started.
d. Of a radio or (transf.) its user: to transmit radio waves owing to faulty operation.
1921Wireless World 29 Oct. 481/1 For a set to ‘react’ or ‘oscillate’ it is necessary that the main inductance and the reaction coil should be so connected that the direction of windings bear a certain relation to one another. 1926Westm. Gaz. 3 Feb. 3/1 Listeners-in who oscillate may find themselves deprived of their licences. 1933‘R. Stranger’ Elem. Wireless xxxvi. 181 A good way of telling when a receiver is oscillating is to have a milliammeter connected in the anode circuit of the detector... Without the milliammeter you may oscillate and not even know it. 1943C. L. Boltz Basic Radio xiv. 222 An interesting effect is observable if the tuning condenser is used when the receiver is oscillating.
2. fig. To fluctuate between two opinions, principles, purposes, etc., each of which is held in succession; to vary between two limits which are reached alternately.
a1797Burke Powers Juries Prosec. Libels Wks. 1877 VI. 161 If they will oscillate backward and forward between power and popularity. 1820Hazlitt Lect. Dram. Lit. 340 The language oscillates between bombast and bathos. 1860Hartwig Sea & Wond. i. 13 The temperature of the surface-water oscillates..between 82° and 85°. 1875Jowett Plato III. 23 Human nature oscillates between good and evil.
3. trans. To cause to swing or vibrate to and fro.
1766F. Blackburne Confess. iii. 56 The Remonstrants, who oscillate the question backwards and forwards till no mortal can find out what they mean. 1858Greener Gunnery 129 Lancaster's oval shell, oscillated in its flight, took a flight so extraordinary. 1883Phil. Trans. R. Soc. CLXXIII. 663 The ring (with wire circuit open) was oscillated backwards and forwards. 1905Preece & Sivewright Telegraphy (new ed.) 462 The spark gap which oscillates the energy.
4. intr. Math. To increase and decrease alternately as successive terms are taken (in the case of a series) or as the variable tends to infinity (in the case of a function).
1898Harkness & Morley Introd. Theory Analytic Functions viii. 102 In the series (1-1) + (1-1) + (1-1)+{ddd}, each term is 0 and the limit is 0, but the series 1-1 + 1-1 +{ddd}oscillates. 1940C. A. Stewart Adv. Calculus i. 7 n2 cos nπ, n + (- 1)nn3 oscillate infinitely. 1973D. G. Ball Introd. Real Anal. iii. 43 A sequence which has no limit at all is said to oscillate. |