Within the Replace Media function the Content Information and Preservation Description Information (PDI) must not be altered.

在替换介质功能中，内容信息和保存描述信息(PDI)绝对不能改变。

youdao

The measuring tube allows the empty state so as to reduce corrosion and fouling of the poles caused by the corrosive media and to reduce the maintenance and preservation cost.

测量管允许空管状态，能减少腐蚀性介质对电极的腐蚀和产生结垢，减少维护保养成本。

youdao

The training emphasized the need to enhance the role of the government, NGOs, communities and media in the identification, inventory and preservation of ICH.

UNESCO: Culture Sector - Intangible Heritage - 2003 Convention

Heritage preservation has always required tremendous efforts, but audiovisual records are far more endangered and more than other media necessitate greater measures for their protection.

UNESCO: Communication and Information