The last part is about the disadvantages of litigation contract, and prove the essentialness for setting up some districting measures on litigation contract.
In this paper, it is discussed that non-central hole rotors essentialness and its advantage through studying the reason of adopting central hole rotor and its disadvantage.
从分析转子中心孔的由来及中心孔的缺点，阐述了无中心孔的必要性和优越性。
3
Firstly, based on DLIO and the summarization of metadata, this paper illustrates the organization structure of DL's information resources, the essentialness of metadata's application in DLIO.