现场总线是用于过程控制现场仪表与控制室之间的一个标准的、开放的、双向的多站数字通信系统。随着计算机技术、通讯技术、集成电路技术的发展，以全数字式现场总线（FIELDBUS）为代表的互联规范，正在迅猛发展和扩大。由于采用现场总线将使控制系统结构简单，系统安装费用减少并且易于维护；用户可以自由选择不同厂商、不同品牌的现场设备达到最佳的系统集成等一系列的优点，现场总线技术正越来越受到人们的重视。--Fieldbus is a standard, open, bi-directional multiple station digital communication system between field equipments and control room.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002060s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.096394s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001300s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001168s ]
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SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000904s ]
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