【摘 要】
：
对借书中常见的续借现象进行分析,续借可以延长持有书籍的时间,但存在续借之前被其他读者预约而使续借失效的可能性.文章考察何时续借是最优的,为此从最简单的泊松流、一次续
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对借书中常见的续借现象进行分析,续借可以延长持有书籍的时间,但存在续借之前被其他读者预约而使续借失效的可能性.文章考察何时续借是最优的,为此从最简单的泊松流、一次续借模型出发,扩展到一般分布和允许多次续借的模型.结果发现最优规则有赖于读者到达的分布,导出了最优续借时刻由风险率函数决定的关系.对于多次续借模型,给出了一般分布时的递推关系式,并得到泊松流情况下的显式解.此模型可以用来描述设备大修等多种管理现象.
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