| 释义 |
persistence|pəˈsɪstəns|
Also 6–9 -ance.
[In 16th c. a. F. persistance (cf. resistance); subseq. changed to -ence after L. persistentem: cf. next.]
1. The action or fact of persisting; firm or obstinate continuance in a particular course in spite of opposition. Also, The quality of being persistent; = persistency.
1546Bale 1st Exam. Anne Askewe 1 A faste membre of Christ by her myghtye persystence in hys veryte. 1633Bp. Hall Hard Texts Jer. xiii. 23 After so long and obstinate persistance in your wickednesse. 1786Burke W. Hastings Wks. 1842 II. 156 Such further evils, as must have been consequent on a persistance therein. 1844Marg. Fuller Wom. 19th C. (1862) 24 Persistence and courage are the most womanly no less than the most manly qualities. 1874Green Short Hist. viii. §2. 472 The refusal of supplies was met by persistence in the levy of Customs.
2. a. Continued existence in time or (rarely) in space; endurance; continuous occurrence.
1621Rachel Speght Frailty of Life, Man is in sacred writ compar'd to grasse,..Of short persistance, like an Aprill showre. 1849Murchison Siluria v. 103 A geological band of great persistence. 1879H. George Progr. & Pov. Introd. (1881) 11 Political economy..does not explain the persistence of poverty amid advancing wealth. 1880Carpenter in 19th Cent. Apr. 599 The persistence of a..number of cretaceous types..through the whole of the Tertiary period.
b. spec. persistence of an impression: the continuance of a sensible impression after the exciting cause is removed, esp. of a visual impression upon the retina of the eye, the cause of many phenomena in optics. persistence of force or energy, persistence of matter, names for the two principles of the conservation of energy and the permanence of matter. persistence of an impression (also simply persistence): used chiefly with reference to vision (so persistence of vision).
1862H. Spencer First Princ. ii. viii. 251 note, I expressed to..Prof. Huxley my dissatisfaction with the current expression—‘Conservation of force’... Huxley suggested persistence. Ibid. (1867) 189 By the persistence of Force, we really mean the persistence of some Power which transcends our knowledge and conception... In other words, asserting the persistence of Force, is but another mode of asserting an Unconditioned Reality. 1869Tyndall Notes Lect. Light 27 An electric spark is sensibly instantaneous; but the impression it makes upon the eye remains for some time after the spark has passed away... Wheatstone's Photometer is based on this persistence. 1883A. Barratt Phys. Metempiric 81 The persistence of matter and energy, and the law..that events happen equally well in all parts of space where their conditions occur, prove that time and space have no real existence, but are only forms of arrangement of phenomena. 1902Encycl. Brit. XXVII. 95/1 Cinematograph... This apparatus shows in rapid sequence a series of views representing closely successive phases of a moving object, and persistence of vision creates the illusion that the object is in motion. 1924J. P. C. Southall tr. H. von Helmholtz's Treat. Physiol. Optics II. 228 The best way to realize this persistence of the impression is to turn the eye to a perfectly dark field after it has been gazing at bright objects. 1944R. W. Moncrieff Chem. Senses iii. 56 Although it has not been measured the persistence of odour must be short like that of taste. 1952Pirenne & Abbott tr. Piéron's Sensations iv. iii. 283 It is generally stated that visual sensations have a persistence of a tenth of a second. 1966C. W. Wilman Seeing & Perceiving vi. 52 Persistence of vision is one reason..why a series of pictures presented at short intervals produces a satisfactory effect in the cinema.
c. (The duration of) the emission of light by a luminescent substance after the cause of the luminescence has ceased; persistence characteristic (see quot. 19501).
1917Physical Rev. IX. 297 It appears that the persistence of luminescence is due to the consistency of the substance and disappears as the fluidity increases. 1935Proc. IRE XXIII. 1325 Slight changes in either the screen material or the method of manufacture may result in large changes..in the persistence with which the light continues to emanate from the excited portion of the screen after the electron beam has been removed. Ibid., Screens which have a short persistence are desired for recording on moving film. Ibid. 1341 The persistence characteristic is taken by the use of some form of stroboscopic apparatus by means of which one is able to measure the relative brilliance of the screen at definite times after excitation. 1950Rider & Uslan Encycl. Cathode-Ray Oscilloscopes vii. 157/1 A plot of the brightness..versus the decay time of the phosphorescence is termed the persistence characteristic of the screen. 1950H. W. Leverenz Introd. Luminescence of Solids v. 150 For (conventional) luminescence emissions, all persistences longer than about 10-8 sec are called phosphorescence to indicate an abnormal delay. 1967Electronics 6 Mar. 127/1 In the 710B, the top scope is coated with P7 phosphor for good persistence. |