Dynamic Programming on Nominal Graphs

Many optimization problems can be naturally represented as (hyper) graphs, where vertices correspond to variables and edges to tasks, whose cost depends on the values of the adjacent variables. Capitalizing on the structure of the graph, suitable dynamic programming strategies can select certain orders of evaluation of the variables which guarantee to reach both an optimal solution and a minimal size of the tables computed in the optimization process. In this paper we introduce a simple algebraic specification with parallel composition and restriction whose terms up to structural axioms are the graphs mentioned above. In addition, free (unrestricted) vertices are labelled with variables, and the specification includes operations of name permutation with finite support. We show a correspondence between the well-known tree decompositions of graphs and our terms. If an axiom of scope extension is dropped, several (hierarchical) terms actually correspond to the same graph. A suitable graphical structure can be found, corresponding to every hierarchical term. Evaluating such a graphical structure in some target algebra yields a dynamic programming strategy. If the target algebra satisfies the scope extension axiom, then the result does not depend on the particular structure, but only on the original graph. We apply our approach to the parking optimization problem developed in the ASCENS e-mobility case study, in collaboration with Volkswagen. Dynamic programming evaluations are particularly interesting for autonomic systems, where actual behavior often consists of propagating local knowledge to obtain global knowledge and getting it back for local decisions.Comment: In Proceedings GaM 2015, arXiv:1504.0244

Engineering and implementing software architectural patterns based on feedback loops

A highly decentralized system of autonomous service components consists of multiple and interacting feedback loops which can be organized into a variety of architectural patterns. The highly complex nature of these loops make engineering and implementation of these patterns a very challenging task. In this paper, we present SimSOTA - an integrated Eclipse plug-in to architect, engineer and implement self-adaptive systems based on our feedback loop-based approach. SimSOTA adopts model-driven development to model and simulate complex self-adaptive architectural patterns, and to automate the generation of Java-based implementation code. The approach is validated using a case study in cooperative electric vehicles

An Integrated Eclipse Plug-In for Engineering and Implementing Self-Adaptive Systems

A highly decentralized system of autonomous service components consists of multiple and possibly interacting feedback loops. These loops can be organized into a variety of architectural patterns. Although several authors have addressed the need to make feedback loops first-class entities, little attention has been given to providing solid tool support for their engineering and implementation. In this paper, we present SimSOTA - an integrated Eclipse plug-in tool to architect, engineer and implement self-adaptive systems based on our feedback loop-based approach. SimSOTA adopts model-driven development to model and simulate complex self-adaptive architectural patterns, and to automate the generation of Java-based implementation code for the patterns. The approach is validated using a case study in cooperative electric vehicles

A Life Cycle for the Development of Autonomic Systems: The e-Mobility Showcase

Abstract—Component ensembles are a promising way of building self-aware autonomic adaptive systems. This approach has been promoted by the EU project ASCENS, which develops the core idea of ensembles by providing rigorous semantics as well as models and methods for the whole development life cycle of an ensemble-based system. These methods specifically address adaptation, self-awareness, self-optimization, and continuous system evolution. In this paper, we demonstrate the key concepts and benefits of the ASCENS approach in the context of intelligent navigation of electric vehicles (e-Mobility), which itself is one of the three key case studies of the project. I

The development of morality

SIGLEAvailable from British Library Document Supply Centre-DSC:DX192519 / BLDSC - British Library Document Supply CentreGBUnited Kingdo