Yet many do not have the time or the tools to carry out such research, which is a complex undertaking as there is no central register of art ownership.

但是，许多人都没有时间或者途径来进行这种调查。因为没有集中的艺术品所有权登记处，所以开展这种调查极为复杂。

youdao

The simplest way is to have participants register the URL of their FOAF file with a central service, which then does the aggregation.

最简单的方法是让参与者通过中央服务注册其 FOAF 文件的 URL，然后中央服务执行聚集。

youdao

New approaches are harder for countries that do not keep a central population register.

对于没有保存中央人口档案的国家来说，采用新方法要困难一些。

youdao

And he said he was campaigning for a central register in Wales to identify where asbestos is present so that it can be monitored.

BBC: Cwmcarn High School: Asbestos exposure warning

She urged the executive to provide a central register of services to give addicts and concerned friends and families instant access to what was available.

BBC: NEWS | UK | Scotland | Goldie lambasts methadone system

France has a central register of residence permits given to aliens.

ECONOMIST: Migration statistics