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—WirelessHART is a new wireless sensor-actuator network standard specifically developed for process industries. A key challenge faced by WirelessHART networks is to meet the stringent real-time communication requirements imposed by process monitoring and control applications. Fixed-priority scheduling, a popular scheduling policy in real-time networks, has(More)
WirelessHART is an open wireless sensor-actuator network standard for industrial process monitoring and control that requires real-time data communication between sensor and actuator devices. Salient features of a Wire-lessHART network include a centralized network management architecture, multi-channel TDMA transmission, redundant routes, and avoidance of(More)
With the advent of industrial standards such as WirelessHART, process industries are now gravitating towards wireless control systems. Due to limited bandwidth in a wireless network shared by multiple control loops, it is critical to optimize the overall control performance. In this article, we address the scheduling-control co-design problem of determining(More)
The WirelessHART standard has been specifically designed for real-time communication between sensor and actuator devices for industrial process monitoring and control. End-to-end communication delay analysis for WirelessHART networks is required for acceptance test of real-time data flows from sensors to actuators and for workload adjustment in response to(More)
Web service composition (WSC) is the task of combining a chain of connected single services together to create a more complex and value-added composite service. Quality of service (QoS) has been mostly applied to represent nonfunctional properties of web services and differentiate those with the same functionality. Many research has been done on QoS-aware(More)
Best-first search is one of the most fundamental techniques for planning. A heuristic function is used in best-first search to guide the search. A well-observed phenomenon on best-first search for planning is that for most of the time during search, it explores a large number of states without reducing the heuristic function value. This phenomenon, called "(More)
Interference between concurrent transmissions can cause severe performance degradation in wireless sensor networks (WSNs). While multiple channels available in WSN technology such as IEEE 802.15.4 can be exploited to mitigate interference, channel allocation can have a significant impact on the performance of multi-channel communication. This paper proposes(More)
Search is a major technique for planning. It amounts to exploring a state space of planning domains typically modeled as a directed graph. However, prohibitively large sizes of the search space make search expensive. Developing better heuristic functions has been the main technique for improving search efficiency. Nevertheless, recent studies have shown(More)
To maximize the channel utilization, an opportunistic spectrum access (OSA) strategy for a slotted secondary user (SU) overlaying an unslotted primary network under interference constraint (IC) and energy consumption constraint (ECC) is proposed. The IC is modeled by the average temporal overlap between SU and PU. On the other hand, since SU is periodic,(More)