A Semantics of Business Configurations Using Symbolic Graphs

In this paper we give graph-semantics to a fundamental part of the semantics of the service modeling language SRML: business configurations. To achieve this goal we use symbolic graph transformation systems. We formalize the semantics using this graph transformation system and illustrating it with a simple running example of a trip booking agent.Peer Reviewe

A graph-semantics of business configurations

In this paper we give graph-semantics to a fundamental part of the semantics of the service modeling language SRML. To achieve this goal we develop a new graph transformation system for what we call 2-level symbolic graphs. These kind of graphs extend symbolic graphs with a simple 2-level hierarchy that can be generalized to arbitrary hierarchies. We formalize the semantics using this new graph transformation system using a simple example of a trip booking agent.Postprint (published version

A graph semantics for a variant of the ambient calculus more adequate for modeling SOC

In this paper we present a graph semantics of a variant of the well known ambient calculus. The main change of our variant is to extract the mobility commands of the original calculus from the ambient topology. Similar to a previous work of ours, we prove that our encoding have good properties. We strongly believe that this variant would allow us to integrate our graph semantics of our mobile calculus with previous work of us in service oriented computing (SOC). Basically, our work on SOC develops a new graph transformation system which we call temporal symbolic graphs. This new graph formalism is used to give semantics to a design language for SOC developed in an european project, but it could also be used in connection with other approaches for modeling or specifying service systems.Postprint (published version

A Framework of hierarchical graphs and its application to the semantics of SRML

Hierarchical grapsh or, in general, hierarchical graph structures are needed when describing visual models at different levels of abstraction. This is the case of the semantic model of SRML, the service modeling language of the european project SENSORIA. In particular, the state model of this language is considered at two level of abstraction. Roughly, at the lowest level, a state configuration is a graph consisting of interconnected components and, at the highest level, business configurations are graphs consisting of interconnected activities, where each activity is a graph of components. Then, a state configuration is the flattening of the corresponding business configuration. Following these ideas, in this paper, we present a new framework of hierarchical graphs, showing that it is m-adhesive. Then we show how this framework can be used to define (part of) a graph transformation semantics of SRML.Postprint (published version

Access Control Synthesis for Physical Spaces

Access-control requirements for physical spaces, like office buildings and airports, are best formulated from a global viewpoint in terms of system-wide requirements. For example, "there is an authorized path to exit the building from every room." In contrast, individual access-control components, such as doors and turnstiles, can only enforce local policies, specifying when the component may open. In practice, the gap between the system-wide, global requirements and the many local policies is bridged manually, which is tedious, error-prone, and scales poorly. We propose a framework to automatically synthesize local access control policies from a set of global requirements for physical spaces. Our framework consists of an expressive language to specify both global requirements and physical spaces, and an algorithm for synthesizing local, attribute-based policies from the global specification. We empirically demonstrate the framework's effectiveness on three substantial case studies. The studies demonstrate that access control synthesis is practical even for complex physical spaces, such as airports, with many interrelated security requirements

The cat's cradle network

In this paper we will argue that the representation of context in knowledge management is appropriately served by the representation of the knowledge networks in an historicised form. Characterising context as essentially extra to any particular knowledge representation, we argue that another dimension to these be modelled, rather than simply elaborating a form in its own terms. We present the formalism of the cat's cradle network, and show how it can be represented by an extension of the Pathfinder associative network that includes this temporal dimension, and allows evolutions of understandings to be traced. Grounding its semantics in communities of practice ensures utility and cohesiveness, which is lost when mere externalities of a representation are communicated in fully fledged forms. The scheme is general and subsumes other formalisms for knowledge representation. The cat's cradle network enables us to model such community-based social constructs as pattern languages, shared memory and patterns of trust and reliance, by placing their establishment in a structure that shows their essential temporality

A Boxology of Design Patterns for Hybrid Learning and Reasoning Systems

We propose a set of compositional design patterns to describe a large variety of systems that combine statistical techniques from machine learning with symbolic techniques from knowledge representation. As in other areas of computer science (knowledge engineering, software engineering, ontology engineering, process mining and others), such design patterns help to systematize the literature, clarify which combinations of techniques serve which purposes, and encourage re-use of software components. We have validated our set of compositional design patterns against a large body of recent literature.Comment: 12 pages,55 reference