As we did for USERNAME in the previous step, set the value as required on the validation TAB, and set the control up to display validation error messages in an error message control.

如我们上一步对USERNAME做的一样，将验证选项卡上的值设为必须，然后在错误消息控制中设定显示验证错误消息。

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Combine blur control with general PID control, on line self-adjusting PID parameters according to different error and error variety-rate, which is called PID parameters self-tuning blur controller.

将模糊控制与常规pid控制相结合，根据不同的误差、误差变化率对PID的参数进行在线自动调整，这就是PID参数自整定模糊控制器。

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Research is made on realization of automatic compensation and control of the error, and a newly developed automatic hole error compensation and control system is introduced.

文章对如何实现该项误差的自动补偿控制进行了研究，并介绍一套新研制的孔径误差自动补偿控制系统。

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The mobile HDVC system delivers high-definition visuals with MPEG4-AVC technology and features 360-degree full duplex stereo sound quality, stable connectivity with QoS, and rate control forward error correction.

ENGADGET: Panasonic and Verizon team up to Mobile HD Visual Communications System using LTE

Rangers' slick passing kept the visitors in control following that goalkeeping error.

BBC: Old Firm in thrilling draw

However, as index-based mutual funds and ETFs continue to gain popularity and active managers are increasingly pressured to control their performance tracking error relative to benchmark indexes, the markets could become less efficient.

FORBES: Equal-Weight Indexers Didn't Suck Wind For A Decade