In online information retrieval on data files for the literature through DIALOG, ORBIT, BRS, QUESTEL, INKA, ISI Search Network and CAS ONLINE systems, the output rate of online prints with a high-speed terminal (1,200bps) is ca. 3.8 times that of online prints with a low-speed terminal (300bps); however, in practice, the overall retrieval time with the high-speed terminal is shorter only by ca. 30 to 60% and the charge fee is lower by ca. 20 to 60% than those with the low-speed terminal. This is because both terminals are almost the same in the reading rate of a searcher for the output data from the systems and the input time for commands. Therefore, as the number of output data is increased, the retrieval with a high-speed terminal becomes greatly advantageous over that with a low-speed terminal owing to the less effect of the reading rate and input time. On the other hand, in the online information systems of CAS ONLlNE, DARC and CIS which can produce figures such as structural formula and spectral charts, these systems do not show so much difference in the retrieval time and charge fee between high-speed and low-speed terminals as described above on the data files for the literature. But, if these systems limit the output in alpha-numeric information, they show the same results as the data files for the literature.
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