中文摘要：

在移动社交网络中，具有相似兴趣爱好的移动用户之间可通过移动计算设备连接起来，形成虚拟社区，它们常需要和基站及社区内其他用户间交互以实现数据内容的传送与分发．因此需要提供高效、低费用的内容分发机制，来及时更新移动社交网络中用户所携带的内容．该文将社区内当前处于邻近物理位置的用户组成临时的虚拟用户组，并以协作的方式通过基站从内容服务商处下载内容，然后在组内完成内容分发．在对用户组的内容传播时间和支付费用这两方面进行优化时，该文首先分析了面向内容分发完成时间的两种优化策略：用户组中内容分发的最大传播时间最小化策略、非服务性用户的内容平均传播时间最小化策略．在此基础上，综合考虑所需支付的内容获取费用与网络连接费用，来制定优化的内容分发机制．该文给出了相应的算法，并通过仿真实验分析了所提出方法的特点．

英文摘要：

In mobile social network, mobile users with common interests can form a virtual com- munity and interact with other ones and base station so as to accomplish the contents distribution among themselves. Some efficient and low-fee mechanisms are needed to help mobile users update their contents carried in a timely manner. In this paper, the mobile users interested in the same content are formed into a virtual group based on their physical proximities. Mobile users down- load and distribute the contents in a cooperative manner among themselves. To reduce the total amount of payment and time consumed by the mobile user group during data distribution, we pro- pose two optimal mechanisms, the one of minimizing the maximal time needed in content distribu- tion and the one of minimizing the average time needed in content distribution. Based on the two strategies, we take into consideration the payment consumed in downloading the data contents and maintaining the wireless linking with base station, and devise several mechanisms for distrib- uting data contents. The corresponding algorithms are designed and experiments are conducted to illustrate the features of our methods.