Nico Nachtigall

On an Automated Translation of Satellite Procedures Using Triple Graph Grammars

Model transformation based on triple graph grammars (TGGs) is a general, intuitive and formally well defined technique for the translation of models [5,6,2]. While previous concepts and case studies were focused mainly on visual models of software and systems, this article describes an industrial application of model transformations based on TGGs as a powerful technique for software translation using the tool Henshin [1]. The general problem in this scenario is to translate source code that is currently in use into corresponding source code that shall run on a new system. Up to now, this problem was addressed based on manually written converters, parser generators, compiler-compilers or meta-programming environments using term rewriting or similar techniques (see e. g. [4]).

Triple Graph Grammars in the Large for Translating Satellite Procedures

Software translation is a challenging task. Several requirements are important – including automation of the execution, maintainability of the translation patterns, and, most importantly, reliability concerning the correctness of the translation. Triple graph grammars (TGGs) have shown to be an intuitive, welldefined technique for model translation. In this paper, we leverage TGGs for industry scale software translations. The approach is implemented using the Eclipse-based graph transformation tool Henshin and has been successfully applied in a large industrial project with the satellite operator SES on the translation of satellite control procedures. We evaluate the approach regarding requirements from the project and performance on a complete set of procedures of one satellite.

On Modelling Communication in Ubiquitous Computing Systems using Algebraic Higher Order Nets

Ubiquitous computing systems (UCSs) are designed to participate almostimperceptibly in everyday life. To ensure a solid operation, a UCS heavily depends on a reliable and efficient communication between its distributed computing components. Moreover components can join and leave the system at any time.In order to guarantee high quality systems, the use of models is inevitable especiallyat an early stage of the development process where models are the only possibilityto address a system which does not yet exist in reality. Petri nets and graph transformationsystems are established, theoretically well-founded concepts for modellingand analysing complex systems.This paper presents a formal approach for modelling core aspects of the communicationin UCSs by using Algebraic Higher Order Nets with Individual Tokens andgraph transformation. The approach is suitable to cover the different aspects ofcommunication and enables the analysis of specific properties. The approach and itssuitability are illustrated based on a running example. The feasibility of embeddingthe approach in a broader context of modelling is demonstrated in applying it to areal world system: the Living Place Hamburg.

Transformation Systems with Incremental Negative Application Conditions

In several application areas, Graph Transformation Systems (GTSs) are equipped with Negative Application Conditions (NACs) that specify “forbidden contexts”, in which the rules shall not be applied. The extension to NACs, however, introduces inhibiting effects among transformation steps that are not local in general, causing a severe problem for a concurrent semantics. In fact, the relation of sequential independence among derivation steps is not invariant under switching, as we illustrate with an example. We first show that this problem disappears if the NACs are restricted to be incremental. Next we present an algorithm that transforms a GTS with arbitrary NACs into one with incremental NACs only, able to simulate the original GTS. We also show that the two systems are actually equivalent, under certain assumptions on NACs.