无效数据

This dissertation fistly introduces appearance, definition, development process, functions and status of MES, also analyses methods and existent problems of MES production scheduling; as follow, in the background of CY_MES (a enterprise's Manufacturing Execution System), introduces main function and buildup of its support platform– SIMATIC IT, and whole structure of CY_MES; afterwards, for special production instance of the enterprise, designs production scheduling system software structure, function structure, data structure of order and entry and realization of silk production and packing production scheduling based on SIMATIC IT; finally, after contrast of many modeling methods and careful research of silk production flow of the enterprise, selects Petri net to model the silk production scheduling, for the sake of avoiding many error chromosomes, improves on the basic genetic algorithm, uses sigle unit genetic algorithm to optimize the Petri net model, lists the contrast of scheduling results.

本文首先介绍了MES的产生、定义、发展历程、功能及其发展现状，同时也分析了MES生产调度问题的各种解决方法及其存在的问题；接着以CY_MES为背景介绍了其支撑平台——SIMATIC IT平台的功能及其各组成部分，以及CY_MES的SIMATIC IT整体解决方案；紧接着在SIMATIC IT平台基础上，针对该烟厂的生产实际情况，设计了CY_MES生产调度系统的软件结构、功能结构、工单和子工单的数据结构和制丝与卷包生产调度的实现方式；最后，在比较了各种生产调度建模方法的利弊和对该烟厂制丝生产工艺流程深入研究后，利用Petri网建立了制丝生产调度模型，为了避免大量无效个体的出现，对基本遗传算法进行了改进，采用单个体遗传算法对这个Petri网模型进行了优化，并给出了调度结果的对比。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。