Web Data Aggregation in MOLAP： Approach,Language, and Implementation

This paper investigates the Web data aggregation issues in multidimensional on-line analytical processing (MOLAP) and presents a rule-driven aggregation approach. The core of the approach is defining aggregate rules. To define the rules for reading warehouse data and computing aggregates, a rule definition languagearray aggregation language (AAL) is developed. This language treats an array as a function from indexes to values and provides syntax and semantics based on monads. External functions can be called in aggregation rules to specify array reading, writing, and aggregating. Based on the features of AAL, array operations are unified as function operations, which can be easily expressed and automatically evaluated. To implement the aggregation approach, a processor for computing aggregates over the base cube and for materializing them in the data warehouse is built, and the component structure and working principle of the aggregation processor are introduced.     

地铁变电所综合自动化系统冗余机制研究

论述地铁变电所综合自动化中前端处理器(front end processor,FEP)与间隔层设备的冗余机制,对典型设备的冗余特点以及集中式和分布式冗余方案进行了讨论和比较,重点分析常规冗余方案存在的问题,并提出改进的方法.     

基于ARM的回转式起货机安全监控系统的研发

工作状态的监控是保障回转式起货机安全工作的重要手段。采用ARM9系列的S3C2440处理器及Linux操作系统作为控制核心,采用液晶触摸屏及Mini GUI设计图形界面作为人机交互,完成了实验室的船舶液压起货机安全监控系统的开发。经现场测试表明:该系统人机交互友好,能实现起重量、工作半径等多个状态参数的实时检测与显示,可根据起重量等级进行报警或停机保护处理。     

盾构管片钢筋笼自动加工设备设计及应用技术研究

为解决盾构管片钢筋笼采用人工加工方法人力投入大、加工质量不稳定和安全风险高等难题,开发自动加工设备已是迫在眉睫。以长株潭城际铁路CZTZH-1标工程为依托,通过对盾构管片钢筋笼生产工艺和钢筋加工设备进行系统分析和研究,确定棒材钢筋剪切、单片网成型、物料存储和立体网焊接成型等系统模块的设计方案和参数,完成设备加工制造、工程现场应用以及优化改进,形成有效的流水作业生产线,从而解决盾构管片钢筋笼自动加工的难题,实现加工机械化和自动化,有效降低劳动强度,提高安全性,且焊接质量稳定可控。