When periodic signals are analyzed in the laboratory, we measure the frequency spectrum of signals usually by a selection level meter.

在实验室进行周期信号分析时，通常使用选频电平表来测量其频谱。

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This is interesting in as much as it shows how such thinking has changed over the years, but her real purpose seems to be to create doubt in the reader's mind about whether selection at the level of the gene is the only mechanism of evolution, which is what Mr Dawkins and his fellow selfish-geners believe.

ECONOMIST: Richard Dawkins under fire

Former education minister Martin McGuinness had moved to abolish the current secondary level education selection system hours before he left office in October last year.

BBC: NEWS | UK | Northern Ireland | Minister receives 11-plus report

Because selection was done at the local level by panels made up of parents, teachers and other members of each community, including non-government organizations, misallocation has been minimal.

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