Abstract-The advent of Service-Oriented Architecture (SOA) in the automation domain has made possible the cross-layer vertical integration of devices, manufacturing systems and business processes. However, the use of standard web service technologies is not always possible in an industrial environment with high real-time requirements and limited hardware resources due to the overhead connected to XML processing. The work presented in this paper analyses the opportunities, advantages and challenges when applying the newly emerged Efficient XML Interchange (EXI) standard for XML encoding to the factory automation systems. The two major SOA-based automation middleware architectures, namely OPC Unified Architecture (OPC UA) and Devices Profile for Web Services (DPWS), were investigated. Furthermore, we present an EXI-based approach for extending the reach of the service technology covering deployments on resource constrained embedded devices.

Abstract-In this paper, we investigate the performance of cluster-based localization using received signal strength indicator (RSSI). The proposed solution is designed to meet the requirements of monitoring of firefighters or similar applications. The empirical relationship between signal strength and distance is determined using experiment data. One of the most popular localization algorithms found today, Min-Max, is used for our testbeds. Our solution is implemented in TinyOS and experimentally evaluated on a Mulle v5.2 IEEE 802.15.4 platform. The aim of our research is to develop a heterogeneous wireless sensor network consisting of inter connected body area networks, or clusters. Using localization, the network's robustness and reliability, as well as the safety of its users, can be improved.

Hardwired sensor installations using proprietary protocols found in today's district heating substations limit the potential usability of the sensors in and around the substations. If sensor resources can be shared and re-used in a variety of applications, the cost of sensors and installation can be reduced, and their functionality and operability can be increased. In this paper, we present a new concept of district heating substation control and monitoring, where a service oriented architecture (SOA) is deployed in a wireless sensor network (WSN), which is integrated with the substation. IP-networking is exclusively used from sensor to server; hence, no middleware is needed for Internet integration. Further, by enabling thousands of sensors with SOA capabilities, a System of Systems approach can be applied. The results of this paper show that it is possible to utilize SOA solutions with heavily resource-constrained embedded devices in contexts where the real-time constrains are limited, such as in a district heating substation.

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Abstract-In this paper, a fully operational wireless sensor and actuator network is presented. The network has the ability to control a district heating substation to ensure indoors comfort while minimizing energy waste by maximizing heat extraction from the distribution network. Introduced here is the foundation for a systems of systems approach within a district heating application, where several substations cooperate with the heat production plant. Presented are also the first steps to a service oriented architecture (SOA) where sensor nodes in the district heating network can cooperate with other nodes and systems, for example a ventilation control network.