A Rewriting-Logic-Based Technique for Modeling Thermal Systems

This paper presents a rewriting-logic-based modeling and analysis technique for physical systems, with focus on thermal systems. The contributions of this paper can be summarized as follows: (i) providing a framework for modeling and executing physical systems, where both the physical components and their physical interactions are treated as first-class citizens; (ii) showing how heat transfer problems in thermal systems can be modeled in Real-Time Maude; (iii) giving the implementation in Real-Time Maude of a basic numerical technique for executing continuous behaviors in object-oriented hybrid systems; and (iv) illustrating these techniques with a set of incremental case studies using realistic physical parameters, with examples of simulation and model checking analyses.Comment: In Proceedings RTRTS 2010, arXiv:1009.398

Formal Model Engineering for Embedded Systems Using Real-Time Maude

This paper motivates why Real-Time Maude should be well suited to provide a formal semantics and formal analysis capabilities to modeling languages for embedded systems. One can then use the code generation facilities of the tools for the modeling languages to automatically synthesize Real-Time Maude verification models from design models, enabling a formal model engineering process that combines the convenience of modeling using an informal but intuitive modeling language with formal verification. We give a brief overview six fairly different modeling formalisms for which Real-Time Maude has provided the formal semantics and (possibly) formal analysis. These models include behavioral subsets of the avionics modeling standard AADL, Ptolemy II discrete-event models, two EMF-based timed model transformation systems, and a modeling language for handset software.Comment: In Proceedings AMMSE 2011, arXiv:1106.596

Model Checking Classes of Metric LTL Properties of Object-Oriented Real-Time Maude Specifications

This paper presents a transformational approach for model checking two important classes of metric temporal logic (MTL) properties, namely, bounded response and minimum separation, for nonhierarchical object-oriented Real-Time Maude specifications. We prove the correctness of our model checking algorithms, which terminate under reasonable non-Zeno-ness assumptions when the reachable state space is finite. These new model checking features have been integrated into Real-Time Maude, and are used to analyze a network of medical devices and a 4-way traffic intersection system.Comment: In Proceedings RTRTS 2010, arXiv:1009.398

A Methodology for Designing Dynamic Topology Control Algorithms via Graph Transformation

This paper presents a constructive, model-driven methodology for designing dynamic topology control algorithms. The proposed methodology characterizes valid and high quality topologies with declarative graph constraints and formulates topology control algorithms as graph transformation systems. Afterwards, a well-known static analysis technique is used to enrich graph transformation rules with application conditions derived from the graph constraints to ensure that this improved approach always produces topologies that (i) are optimized wrt. to a domain-specific criterion, and (ii) additionally fulfill all the graph constraints

A Probabilistic Strategy Language for Probabilistic Rewrite Theories and Its Application to Cloud Computing

Several formal models combine probabilistic and nondeterministic features. To allow their probabilistic simulation and statistical model checking by means of pseudo-random number sampling, all sources of nondeterminism must first be quantified. However, current tools offer limited flexibility for the user to define how the nondeterminism should be quantified. In this report we propose an expressive probabilistic strategy language that allows the user to define complex strategies for quantifying the nondeterminism in probabilistic rewrite theories. These strategies may depend on the current system state, and their associated weight expressions can be given by any computable function defined equationally in Maude. We have implemented PSMaude, a tool that extends Maude with a probabilistic simulator and a statistical model checker for our language. We illustrate the convenience of being able to define different probabilistic strategies by a cloud computing example, where a (non-probabilistic) rewrite theory defines the capabilities of the cloud computing infrastructure, and where different load balancing policies are specified by different probabilistic strategies. Our language also enables a Maude-based safety/QoS modeling and analysis methodology in which key safety properties can be verified for a basic ``uncluttered'' non-probabilistic model, and where QoS properties for different probabilistic strategies can be analyzed by probabilistic simulation and statistical model checking