Critical Infrastructures (CIs) and their protection play a very important role in modern societies. Today's CIs are managed by sophisticated information systems. These information systems have special views on their respective CIs -but can frequently not manage dependencies with other systems adequately. For dependency analysis and management we need information taking the dependency aspects explicitly into account -in well defined relations to all other relevant kinds of information. This is the aim of the IRRIIS Information Model. It is a semantic model or ontology of CI dependencies. This Information Model allows us to integrate information from different CIs -from real ones as in SCADA systems, or from simulations -in order to manage their interdependencies. This paper gives an overview of the IRRIIS Information Model and the way it is used in the IRRIIS simulator SimCIP for the analysis of interdependent infrastructures. An example will be given to illustrate our approach.

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Cyber-Physical Systems (CPS) are controlled complex technical systems. On one hand they do exist and behave in the physical world with their dedicated physical and technical rules. On the other hand they are controlled according to certain policies - frequently by a "tandem" of control systems and human operators. Modern cars, aircrafts, power grids, production lines etc. are typical cyber-physical systems. The unprecedented technology development has enabled these systems to play an increasingly central role in modern societies. However, to ensure the reliability and effectiveness of CPS operations is always a challenging task since they are often heterogeneous, large-scale and very complex for conventional software systems. In this paper we propose a novel rule-based approach combining deductive and reactive rules to specify and describe CPS. Complex Event Processing (CEP) and Event-Condition-Action (ECA) rules are used to detect situations of interest in CPS and issu ing (complex) control actions, respectively. This allows us to focus on the "what" of CPS control (situation detection, reaction specification) and leaves the "how" to a well defined event and action engine. Whereas events are treated in CPS much the same as in other fields actions are quite different because they happen in the real world. We describe an approach to CPS actions which takes these important particularities into account. Another important issue is the integration of physical models into event and action processing. Temporal aspects play a central role here. Our approach enables us to control CPSs under both normal and exceptional conditions in a flexible and efficient way. In order to illustrate the basic features and expressivities of the proposed approach we consider realistic industrial situations

A previously established theoretical basis for controlling both the static stiffness as well as dynamic vibrations and regenerative chatter in particular was implemented in the work described by this paper. It was found that the experimental boring bar setup did exhibit two principal modes but that the controller could be synthesized largely independent of these modes. Cutting tests were performed using Delrin acetal plastic on a lathe equipped with a pivoted boring bar which was controlled by an electro-hydraulic servo system. It was found that the theory established earlier did in fact predict qualitatively the new stability borderline. Width of cut was improved by a factor of twelve and equivalent static stiffness was increased without bound.

We consider critical infrastructures as cyber-physical systems (CPS). Although simulations play an important role for CPS, no single simulator is available to simulate different depending CI. Therefore, interoperability of simulators in federated simulations is an important requirement. For modelling and simulation of CPS behaviour, both physical and control aspects have to be considered. CPS control is essentially based on events, states and reactions. Today there are mature numerical simulations for physical behaviours, whereas control is frequently treated in a restricted and ad-hoc manner. We present and analyse different simulator integration approaches based on explicit semantic models and show how they improve the modelling and simulation capabilities of federated simulations in CPS. We demonstrate how complex event processing and reactive rules allow the description of CPS behaviour on the event and action level and the integration of control into federated simu lations