Zhang Xueliang had showed great patriotic spirit and a noble character on a few key points of anti-Japanese positions and actions,such as "Northeast Changing-flag,"、"Allying CPC to Anti-Japanese "、"Xi an Incident" and "Sending Jiang Jieshi Back to Nanjing" anti-Japanese.

The key points of their theories are: first, the strategic change in the way the Party maintains its lea.

Study on Key Nodes Control of Project Manufacturing Process;

Appraising method and distributing characteristics of key nodes of enterprise networks responding to customer demand;

Method of recognizing key nodes based on connectivity

Then,the paper puts forward a method that can be used to identify the key buses of Communication Networks which is available to improve its security.

A new sneak circuit analysis method based on the key node topo patterns is put forward.

We proposed a new methed to measure the voltage stability at the key node,which was based on the WAMS to increase power system security.

By taking a H76/95-G115-A-type pump for example,it also discusses about topological structure and key node of the overhaul of a mechanical seal,analyzing its technological measures and points for attention.

As the failure of a critical node will directly partition a network,a theorem for critical node identification was proved,which indicates that node degree Ni and elementary loop degree Mi of node i are two decisive factors for the exis-tence of a critical node and shows that Ni-Mi≥ 2 is the necessary and sufficient condition for node i being critical.