Biblio
The mass integration and deployment of intelligent technologies within critical commercial, industrial and public environments have a significant impact on business operations and society as a whole. Though integration of these critical intelligent technologies pose serious embedded security challenges for technology manufacturers which are required to be systematically approached, in-line with international security regulations.This paper establish security foundation for such intelligent technologies by deriving embedded security requirements to realise the core security functions laid out by international security authorities, and proposing microarchitectural characteristics to establish cyber resilience in embedded systems. To bridge the research gap between embedded and operational security domains, a detailed review of existing embedded security methods, microarchitectures and design practises is presented. The existing embedded security methods have been found ad-hoc, passive and strongly rely on building and maintaining trust. To the best of our knowledge to date, no existing embedded security microarchitecture or defence mechanism provides continuity of data stream or security once trust has broken. This functionality is critical for embedded technologies deployed in critical infrastructure to enhance and maintain security, and to gain evidence of the security breach to effectively evaluate, improve and deploy active response and mitigation strategies. To this end, the paper proposes three microarchitectural characteristics that shall be designed and integrated into embedded architectures to establish, maintain and improve cyber resilience in embedded systems for next-generation critical infrastructure.
A low power consumption three-position four-way direct drive control valve based on hybrid excited linear actuator (HELA-DDCV) was provided to meet the requirements of the response time and the power consumption. A coupling system numerical model was established and validated by experiments, which is based on Matlab/Simulink, from four points of view: electric circuit, electromagnetic field, mechanism and fluid mechanics. A dual-closed-loop PI control strategy for both spool displacement and coil current is adopted, and the process of displacement response was analyzed as well as the power consumption performances. The results show that the prototype valve spool displacement response time is less than 9.6ms. Furthermore, the holding current is less than 30% of the peak current in working process, which reduces the power consumption effectively and improves the system stability. Note that the holding current can be eliminated when the spool working at the ends of stroke, and 0.26 J energy is needed in once action independent of the working time.