基于STM32的居民社区门窗禁控制系统

针对居民社区公共门窗管理不及时,耗费大量人力资源,且效率较低等问题,设计了一款基于STM32单片机的居民社区门窗禁控制系统.在传统的门禁控制系统的基础上,系统利用Zigbee无线传感网技术,实现门窗禁控制器之间的无线通讯.管理用户可以通过以太网远程控制系统,系统也可以根据传感器监测到的环境数据实现自动调节.同时,尝试采用一种基于频率捷变的分布式自适应干扰技术,解决系统在居民居住环境中遇到的Wifi网络信号干扰问题.最后,通过测试表明,该系统运行稳定,具有广泛的应用前景.     

The EU data protection reform and the challenges of big data: remaining uncertainties and ways forward

As the first broad reform of the EU data protection legislation is being achieved, and notwithstanding EU institutions’ confident discourse, scepticism remains about the reform’s ability to safeguard the fundamental right to data protection in the face of evolving data processing techniques underlying so-called big data. Yet, one might wonder whether the cause for this difficulty should be ascribed mainly to technological progresses that the law finds it hard to deal with or rather to the policy choices embedded in the legal reform itself. Indeed, a new data protection enforcement model is being adopted, which relies heavily on risk assessment and management by the data controllers themselves. Likewise, data protection authorities see their supervisory role significantly weakened. These developments and the underlying rationality are discussed. Given the limitations of the risk-based approach as currently devised, we suggest that it be reappraised in consideration of risk regulatory experiences in other domains.     

基于控制器切换的涡扇发动机转速调节及安全保护

本文通过多个控制器间的切换改善了航空发动机加速过程的动态性能,并在转速过高时加以保护。首先,根据航空发动机控制系统模型利用区域极点配置方法对于每个子系统设计一个H∞输出跟踪控制器,并且设计滞后切换规则,使发动机高压转子转速既能快速跟踪参考加速曲线又能保证较小超调,同时由于滞后切换规则的存在避免频繁切换造成的执行机构不必要的损耗;然后设计安全保护控制器及事件触发的切换机制,在高压转子转速过高时保护转速使其不超过最高转速边界,保证飞行安全;最后通过数例仿真验证了本文方法的有效性。     

Cloud computing — The business perspective

The evolution of cloud computing over the past few years is potentially one of the major advances in the history of computing. However, if cloud computing is to achieve its potential, there needs to be a clear understanding of the various issues involved, both from the perspectives of the providers and the consumers of the technology. While a lot of research is currently taking place in the technology itself, there is an equally urgent need for understanding the business-related issues surrounding cloud computing. In this article, we identify the strengths, weaknesses, opportunities and threats for the cloud computing industry. We then identify the various issues that will affect the different stakeholders of cloud computing. We also issue a set of recommendations for the practitioners who will provide and manage this technology. For IS researchers, we outline the different areas of research that need attention so that we are in a position to advice the industry in the years to come. Finally, we outline some of the key issues facing governmental agencies who, due to the unique nature of the technology, will have to become intimately involved in the regulation of cloud computing.     

505E调速器在U-GB151CO2压缩机上的应用

川化股份有限公司化肥厂二化尿素装置为日产2460T尿素的大型化肥装置,其CO2压缩机采用日本三菱3V-7B型两缸四段压缩机,由抽汽注汽冷凝式透平驱动.该透平的转速控制由505E控制器实现,并与ProTech 203相结合实现压缩机的两级超速保护.Woodward 505E数字控制器适用于具有一次可调整的纯抽汽、抽补结合或纯补汽型式透平的控制,可现场编程组态,使标准的设计能适用于各种不同的控制场合.文中介绍了505E控制器在UGB151 CO2压缩机上的调速应用,并例举调速系统出现的故障,进行分析排除.     

高功率因数斩波式串级调速系统的研究

为了克服传统串级调速系统功率因数低的缺点 ,提出了一种新型斩波式串级调速方案。该方案中的逆变电压与逆变电流的夹角可以在 15 0°与 180°之间变动 ,有效地提高了串级调速系统的功率因数     

国产矿井提升机PC电控系统没有完全实现PC化的主要原因及对策

阐述了国产矿井提升机PC电控系统的发展过程及现状 ,指出了其没有完全实现PC化的主要原因 ,并提出了使其完全PC化的对策。最后 ,介绍了提升机制动系统用PC控制的实现方法。     

谈长龙灌区渠道整治措施

本文根据江西省赣州市中型灌区节水配套改造项目原则和要求,针对兴国县长龙灌区渠系及其建筑物目前存在的问题,分别提出了相应的整治措施,为确保灌区渠道输水安全,进一步提高灌区水的利用率和灌溉保证率,从设计方法上提供有益的经验.     

关于平阳县中小河流整治必要性探讨

平阳县河流众多,经济发展迅速,带来的环境负面影响对河流的威胁也随之增加,导致河流人为干扰严重,河流淤积阻塞、水环境恶化、生态功能退化,水土流失严重等结果。因此,急需针对平阳县中小河流存在的问题,有效地开展河流治理工作,恢复河道综合功能、提升行洪排涝能力、沟通水系、改善农村水环境、提高灌溉供水保障程度、加快新农村建设、改善民生、促进人水和谐及城乡经济的可持续发展。