一种双机热备份计算机系统

本文探讨了计算机系统冗余备份的工作原理和实现方法，介绍了一种实用的双机热备份切换、控制系统和其切换、控制单元的组成和工作原理。     

Analysis of the US cruise line industry

The cruise line industry has been through a metamorphosis. From being a declining mode of travel in the 1960s, the cruise line industry turned the corner in the 1970s and became one of the fastest growing segments of the wider tourism industry during the 1980s. This paper examines the reasons behind this growth, the current structure of the US cruise industry and the issues facing the industry in the 1990s as it heads towards the next century.     

Market penetration by entry-exit dynamics

A generic characterization of the dynamics of market penetration by technological artifacts is here formulated on the basis of entry rate and exit rate considerations. It is shown that low-order reductions lead to the biologically based logistic dynamic, which—by empirical fit—has been found to be in very good agreement with numerous specific cases. In addition to the derivational justification of the logistic for artifact market penetration, we find that but a small number of parameters are involved in these autonomous characterizations suggesting therefore that market penetration may well be reduced to a similarly small number of dominant operative processes. Some nonautonomous extensions are also discussed.     

Some economics of content protection

We are grateful to a perceptive referee for many constructive comments on an earlier version of this paper entitled The Economics of Content Protection: A Dual Approach. The usual disclaimer applies.