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921.
Caryl A. Hess 《School science and mathematics》1994,94(4):208-214
The term “computer literacy” became very popular in the 1980s as a catch phrase describing a new type of understanding. Prior to the phrase's popularity, “literacy” was reserved for the knowledge of basic skills in reading and writing and familiarity with the classical works and great books of ancient and modern cultures. To be literate means to be educated regarding the fundamental or basic ideas, beliefs and methods of communication in society. By applying the term “literacy” to the knowledge of computers, society is signifying that this sort of knowledge is as important to a person's education in contemporary society as knowledge of reading and writing has been in the past (Ringle, 1981). While many people seem to agree that the proliferation of computers and their application in extensive areas of human endeavor require us to take the notion of literacy seriously, there is still no consensus as to how this educational goal should be achieved. The difficulty stems from the fact that there is no universally accepted definition of computer literacy. Until educators are clear about the goal, effective ways to attain the objective of computer literacy will be clouded by confusion. The purpose of this research is to examine the historical evolution of the phrase “computer literacy,” to develop a chronological continuum of computer literacy, and to identify several competencies that will likely characterize the computer literate teacher in the 1990s. 相似文献
922.
923.
924.
Nonideal plasmas have been generated by mechanical compression with a so-called ballistic compressor. The Debye numbers reached were 0.4 in argon and 0.2 in xenon. The experimentally determined pressure, specific volume, and temperature are compared with calculations of the compression using different models of the charged particle interaction. This comparison shows that heat losses may take an essential part in the interpretation of the experimental results. 相似文献
925.
A collisional-radiative model of helium has been developed that incorporates the effect of optical pumping with light that is resonant with an atomic transition. A steady-state solution of the collisional- radiative model with no pumping is used as an initial condition. The pumping radiation is switched on, and the population densities of the atomic levels are calculated as a function of time. Results are given for a wide range of plasma parameters and various pumping conditions. 相似文献
926.
927.
The signs of dipole moment derivatives for ethylene oxide obtained from ab initio calculations using the 6-31G1 basis set are presented. From these signs and the experimental vibrational absorption intensity data, the atomic polar tensor elements and bond charge flux parameters were evaluated. These quantities were compared with those in the literature calculations employing approximate signs and force constants. 相似文献
928.
Effects of flanking noise bands on the rate of growth of loudness of tones in normal and recruiting ears 总被引:3,自引:0,他引:3
B C Moore B R Glasberg R F Hess J P Birchall 《The Journal of the Acoustical Society of America》1985,77(4):1505-1513
Five subjects with unilateral cochlear hearing impairments and three normally hearing subjects made loudness matches between tones presented alternately to two ears, as a function of the intensity of the tone in the impaired ear (or the left ear of the normal subjects). The impaired ears showed recruitment; the rate of growth of loudness with increasing intensity was more rapid in the impaired ear than the normal ear. Presenting the tone in the impaired ear with two noise bands on either side of the tone frequency, at a fixed signal-to-noise ratio, did not abolish the recruitment. This suggests that recruitment is not caused by an abnormally rapid spread of excitation in the peripheral auditory system. At low signal-to-noise ratios, a continuous background noise reduced the loudness of the tone more than a noise gated with the tone, suggesting that the continuous noise induces adaptation to the tone. The noise had a greater effect on the loudness of the tone in normal ears than in impaired ears. It is possible that the loudness reduction of the tone in noise is mediated by suppression; suppression is weak or absent in impaired ears, and so the loudness reduction is smaller. 相似文献
929.
930.
Crystal and Molecular Structure of Dimeric Dimethylaminodimethylindium Dimeric dimethylamino-dimethylindium was prepared by splitting off methane from the adduct Me3In? NHMe2 and characterized by its vibrational spectra. The structure – determined by X-ray analysis – has shown to have the monoclinic space group P21/c with a = 7.601, b = 7.336, c = 14.927 Å and β = 119.9°. Patterson, Fourier and Difference synthesis were used for determing the structure, which was refined by least square analysis to an R value of 0.068. 相似文献