In one-dimensional disordered wires electronic states are localized at any energy. Correlations of the states at close positive energies and the AC conductivity \sigma(\omega) in the limit of small frequency are described by the Mott-Berezinskii theory. We revisit the instanton approach to the statistics of wave functions and AC transport valid in the tails of the spectrum (large negative energies). Applying our recent results on functional determinants, we calculate exactly the integral over Gaussian fluctuations around the exact two-instanton saddle point. We derive correlators of wave functions at different energies beyond the leading order in the energy difference. This allows us to calculate corrections to the Mott-Berezinskii law (the leading small-frequency asymptotic behavior of \sigma(\omega)) which approximate the exact result in a broad range of \omega. We compare our results with the ones obtained for positive energies.
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The aim of this study was to understand the motives for using the Internet, and its associations with users' attitudes, social values, and relational involvement. Also, this study attempted to crossculturally compare the difference in the pattern of motives and the associations among three countries ' the US, the Netherlands, and S. Korea. The design of methods was based on examination and revision of uses and gratification approach toward Internet users. Findings from factor analysis revealed that information seeking and Self-Improvement were the dominant and common reasons for using the Internet across three countries. The differences in the composition of motives in each country were also reported. Strong correlations across countries were found between all the motives and satisfaction of the Internet. Expectation and positive evaluation of the Internet were also important attitudes associated with Internet use motives. Postmaterialist value showed strong association with motives of information seeking and Self-Improvement. Community involvement was significantly associated with Internet use motives in Korean users.
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