Abstract
The integration of multiple database technologies, including both SQL and NoSQL, allows using the best tool for each aspect of a complex problem and is increasingly sought in practice. Unfortunately, this makes it difficult for database developers and administrators to obtain a clear view of the resulting composite data processing paths, as they combine operations chosen by different query optimisers, implemented by different software packages, and partitioned across distributed systems. This work addresses this challenge with the X-Ray framework, that allows monitoring code to be added to a Java-based distributed system by manipulating its bytecode at runtime. The resulting information is collected in a NoSQL database and then processed to visualise data processing paths as required for optimising integrated database systems. This proposal is demonstrated with a distributed query over a federation of Apache Derby database servers and its performance evaluated with the standard TPC-C benchmark workload. © IFIP International Federation for Information Processing 2015.

Abstract
The vision of the Internet-of-Things (IoT) embodies the seam- less discovery, configuration, and interoperability of networked devices in various settings, ranging from home automation and multimedia to autonomous vehicles and manufacturing equipment. As these ap- plications become increasingly critical, the middleware coping with Machine-to-Machine (M2M) communication and coordination has to deal with fault tolerance and increasing complexity, while still abiding to resource constraints of target devices. In this paper, we focus on configuration management and coordi- nation of services in a M2M scenario. On one hand, we consider ZooKeeper, originally developed for cloud data centers, offering a simple file-system abstraction, and embodying replication for fault-tolerance and scalability based on a consensus protocol. On the other hand, we consider the Devices Profile for Web Services (DPWS) stack with replicated services based on our implementation of the Raft consensus protocol. We show that the latter offers adequate performance for the targeted applications while providing increasing flexibility.

Abstract
This paper introduces a method to build dynamic logics with a graded semantics. The construction is parametrized by a structure to support both the spaces of truth and of the domain of computations. Possible instantiations of the method range from classical (assertional) dynamic logic to less common graded logics suitable to deal with programs whose transitional semantics exhibits fuzzy or weighted behaviour. This leads to the systematic derivation of program logics tailored to specific program classes.

Abstract
Dynamic logic combines logic with programs, which at a certain level of abstraction, can be regarded as behaviours changing the system state and, therefore, the truth value of formulas. This paper suggests a method for generating such logics for the domain of robot controllers and illustrates it with a logic for handling resource consumption.

Abstract
Continuous evolution towards very large, heterogeneous, highly dynamic computing systems entails the need for sound and flexible approaches to deal with system modification and re-engineering. The approach proposed in this paper combines an analysis stage, to identify concrete patterns of interaction in legacy code, with an iterative re-engineering process at a higher level of abstraction. Both stages are supported by the tools CoordPat and Archery, respectively. Bi-directional model transformations connecting code level and design level architectural models are defined. The approach is demonstrated in a (fragment of a) case study.

Abstract
Adding to the modal description of transition structures the ability to refer to specific states, hybrid(ised) logics provide an interesting framework for the specification of reconfigurable systems. The qualifier 'hybrid(ised)' refers to a generic method of developing, on top of whatever specification logic is used to model software configurations, the elements of an hybrid language, including nominals and modalities. In such a context, this paper shows how a calculus for a hybrid(ised) logic can be generated from a calculus of the base logic and that, moreover, it preserves soundness and completeness. A second contribution establishes that hybridising a decidable logic also gives rise to a decidable hybrid(ised) one. These results pave the way to the development of dedicated proof tools for such logics used in the design of reconfigurable systems.