Energy Efficiency Based on Quality of Data for Cyber Physical Systems

Cyber-Physical Systems (CPS) are convergence of real physical world and computation world. CPS systems are rapidly becoming an important development strategies with broad application domains. The key requirements for CPS systems are to support multiple applications with many different resources at the same time in timeliness and also ensure energy efficiency. This paper presents the Cyber-Physical integrated cloud computing system called Cyber-Physical Cloud (CPC) to solve these key requirements. CPC architecture is designed for various applications such as health care, smart cars, traffic control, etc where multiple wireless sensor networks (WSNs) communicate with each other through mobile ad hoc network. Concurrently, CPC architecture can leverage cloud computing to process effectively computation and resource management by virtualization technique. Moreover, CPS systems are built on heterogeneous WSNs to collect and process the physical objects by obtaining data and thereafter processing queries. As a part of CPS systems, the key requirement for WSNs is to sustain a long lifetime because of limited power supplies. We work on real time preemptive query scheduling in WSNs with a focus on quality of data (QoD) to analysis useful energy consumption and interference energy consumption. We propose the Energy efficiency Aware Quality of Data (EAQD) method that runs on real time preemptive query scheduling to find the expected QoD for each query thus enabling energy consumption minimization. EAQD method also computes the transmitting/receiving slots needed for each query to avoid wasting slots. The simulation results show the our approach can reduce energy consumption up to 5 times as compares to previous approaches.