论网络舆情监测系统的基础设计

网络舆情监测系统实时定向采集主流权威有影响力的微博、新闻、论坛、博客等网站信息,抽取舆情要素,发现舆情热点,挖掘舆情敏感话题,及时预警,追踪发展情况,并研判舆情态势。本文就此进行简要论述。     

基于模型的航电系统研发方法研究

为满足航电系统的结构越来越复杂、系统综合化程度越来越高的需要,提出了基于模型的航电系统研发方法.详细介绍了自顶向下的模型化系统设计、自动化系统的实现以及基于模型的系统仿真和测试方法.通过实际项目的应用和验证,基于模型的航电系统研发方法能够有效地加快设计迭代速度,减轻人工编写代码的工作量,提升研发团队的协同开发能力.     

基于S7-1200PLC的全自动胶带封箱机控制系统设计

针对人工封箱或使用手动胶带封箱机封箱的效率低、工作强度大的问题,设计了一套基于S7-1200 PLC的全自动控制系统,使手动胶带封箱机变为全自动胶带封箱机,能够根据纸箱的尺寸大小自动调节夹紧机构和压紧机构,实现对不同尺寸的纸箱快速封箱。通过实验验证,对尺寸多变的纸箱封箱工作,该全自动胶带封箱机的工作效率高于人工封箱和使用手动胶带封箱机封箱,大大降低了工人劳动强度。     

Feature selection algorithm for text classification based on improved mutual information

In order to solve the poor performance in text classification when using traditional formula of mutual information (MI),a feature selection algorithm were proposed based on improved mutual information.The improved mutual information algorithm,which is on the basis of traditional improved mutual information methods that enhance the MI value of negative characteristics and feature’s frequency,supports the concept of concentration degree and dispersion degree.In accordance with the concept of concentration degree and dispersion degree,formulas which embody concentration degree and dispersion degree were constructed and the improved mutual information was implemented based on these.In this paper,the feature selection algorithm was applied based on improved mutual information to a text classifier based on Biomimetic Pattern Recognition and it was compared with several other feature selection methods.The experimental results showed that the improved mutual information feature selection method greatly enhances the performance compared with traditional mutual information feature selection methods and the performance is better than that of information gain.Through the introduction of the concept of concentration degree and dispersion degree,the improved mutual information feature selection method greatly improves the performance of text classification system.     

论网络舆情监测系统中关键词智能追踪模型的建立

本通过分析舆情信息采集策略,提出智能化的关键词追踪模型,通过关键词智能追踪模型的应用,网络舆情监测系统能及时抓取热点事件的热点关键词,从而实现网络舆情监控系统对热点事件发展趋势的灵敏响应,并为网络舆情热点事件的预警提供数据支持。简单来说关键词智能追踪模型就是以一定的关键词权重算法为基础,依据舆情事件变化速度,通过多次的反复的归纳计算,对之前选取的关键词进行修改、调整和校对的过程。     

结晶器振动液压缸的优化改造

由于国产结晶器振动液压缸(以下简称振动缸)使用寿命普遍较短,严重影响生产,导致国内钢铁企业纷纷选择进口振动缸。虽然价格昂贵,但使用寿命远远超过国产振动缸,明显提高铸坯质量。根据生产和维修记录,总结了振动缸的主要失效形式。分析失效原因,借鉴国外密封技术,采用间隙密封[1]结构,同时对活塞、活塞杆、伺服环[1]和缸筒内壁进行热处理,使其具有摩擦系数小、泄露少等特点,从而提高振动缸的使用寿命。实践证明,该振动缸的使用寿命接近进口振动缸的使用寿命。