但愿太阳能从西边出来

5月5日，正值长假期间。我路过集镇，碰巧遇到我班学生周新科。周新科（化名）和他奶奶手拉手刚好从食品店出门，祖孙俩各自拿着一串油滴滴的炸里脊肉，正大口地咬着，汤汁顺着嘴角向下流。     

课堂 不妨多几分阳刚之气

最近，我听了几节青年教师的评优课。 这几位风华正茂的青年，大多是本市教科研领域里响当当的领军人物。     

一种备件多级库存系统的仿真模型

针对预测性维修（Predictive Diagnostic Maintenance,PDM）策略中维修备件库存优化配置问题,提出了融合故障预测与健康管理（Prognostics and Health Management,PHM）信息的维修备件库存决策方法。在多级库存模型的基础上,建立了基于PHM的维修备件多级库存仿真模型。最后,通过模型求解和Matlab仿真分析,结果表明了基于PHM的维修备件多级库存模型的可行性和有效性。

Abstract：

Aiming at spare parts stock allocation problem under the surrounding of Predictive Diagnostic Maintenance, a new method on spare parts multistage stock system was proposed including the message of Prognostics and Health Management. The PHM-based multistage stock model was built based on model of multistage stock. With the resolving of the model and the simulation by Matlab 7.0., the validity and feasibility of the PHM-based multistage stock model are confirmed.     

Machinery and Equipment Maintenance Strategy and Choice

The advantages, disadvantages and characteristics of various maintenance strategies for modern mechanical equipment are analyzed. Combined with the system structure and functional characteristics of engineering equipment,it puts forward the selection method of maintenance strategies for different types of equipment and failure modes. The view of this article is that the comprehensive maintenance strategy, which is based on condition based maintenance(CBM) and combines various maintenance strategies. This will become the main development direction of engineering equipment maintenance.