The adding system regards the slime water of the free district of the thickener as detecting target, sedimental speed as the feedback, form the close-circuit control system.

该添加系统以浓缩池自由区的煤泥水为检测对象，以沉降速度作为反馈量，构成闭环控制系统。

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UCCA, located at 798 art district, also offers a free art workshop every weekend for children of migrant workers in the capital.

尤伦斯当代艺术中心(UCCA)位于798艺术区，每周还为首都的外来工儿童提供免费的艺术工作室。

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Under the program, the district gives home-schooling families free computers and Internet service for correspondence classes.

按照学校计划，学区为在家从事家庭教育的家庭免费提供函授课程所用的电脑和互连网业务。

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The bill would free all slaves in the district who were born after a certain time.

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The Port Authority is leasing the space to the business improvement district for free, and will maintain it, officials said.

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Abdullah Syafie, a rebel commander of the Free Aceh Movement in Pidie district in northern Aceh, refuses even to speak Bahasa Indonesia--the language that more than anything binds the country together--and a young aide translates his words from Acehnese.

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Two years ago, the Houston Independent School District began offering the SAT free during class time.

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