A CNL for Contract-Oriented Diagrams

We present a first step towards a framework for defining and manipulating normative documents or contracts described as Contract-Oriented (C-O) Diagrams. These diagrams provide a visual representation for such texts, giving the possibility to express a signatory's obligations, permissions and prohibitions, with or without timing constraints, as well as the penalties resulting from the non-fulfilment of a contract. This work presents a CNL for verbalising C-O Diagrams, a web-based tool allowing editing in this CNL, and another for visualising and manipulating the diagrams interactively. We then show how these proof-of-concept tools can be used by applying them to a small example

Semantics through Pictures

A diagrammatic approach to the semantics of OO modelling notations is proposed. This is based on an innovative and expressive notation dubbed ''constraint diagrams'', which can be used to precisely characterise a range of sophisticated, static constraints on OO models. Other notations, such as those found in UML, can be viewed as projections of constraint diagrams. Work on using constraint diagrams at the core of a 3D modelling notation is also briefly described as a means of similarly providing the semantics of diagrams imposing constraints on dynamic behaviour

Towards Practical Graph-Based Verification for an Object-Oriented Concurrency Model

To harness the power of multi-core and distributed platforms, and to make the development of concurrent software more accessible to software engineers, different object-oriented concurrency models such as SCOOP have been proposed. Despite the practical importance of analysing SCOOP programs, there are currently no general verification approaches that operate directly on program code without additional annotations. One reason for this is the multitude of partially conflicting semantic formalisations for SCOOP (either in theory or by-implementation). Here, we propose a simple graph transformation system (GTS) based run-time semantics for SCOOP that grasps the most common features of all known semantics of the language. This run-time model is implemented in the state-of-the-art GTS tool GROOVE, which allows us to simulate, analyse, and verify a subset of SCOOP programs with respect to deadlocks and other behavioural properties. Besides proposing the first approach to verify SCOOP programs by automatic translation to GTS, we also highlight our experiences of applying GTS (and especially GROOVE) for specifying semantics in the form of a run-time model, which should be transferable to GTS models for other concurrent languages and libraries.Comment: In Proceedings GaM 2015, arXiv:1504.0244

Extracting Formal Models from Normative Texts

We are concerned with the analysis of normative texts - documents based on the deontic notions of obligation, permission, and prohibition. Our goal is to make queries about these notions and verify that a text satisfies certain properties concerning causality of actions and timing constraints. This requires taking the original text and building a representation (model) of it in a formal language, in our case the C-O Diagram formalism. We present an experimental, semi-automatic aid that helps to bridge the gap between a normative text in natural language and its C-O Diagram representation. Our approach consists of using dependency structures obtained from the state-of-the-art Stanford Parser, and applying our own rules and heuristics in order to extract the relevant components. The result is a tabular data structure where each sentence is split into suitable fields, which can then be converted into a C-O Diagram. The process is not fully automatic however, and some post-editing is generally required of the user. We apply our tool and perform experiments on documents from different domains, and report an initial evaluation of the accuracy and feasibility of our approach.Comment: Extended version of conference paper at the 21st International Conference on Applications of Natural Language to Information Systems (NLDB 2016). arXiv admin note: substantial text overlap with arXiv:1607.0148

Three Dimensional Software Modelling

Traditionally, diagrams used in software systems modelling have been two dimensional (2D). This is probably because graphical notations, such as those used in object-oriented and structured systems modelling, draw upon the topological graph metaphor, which, at its basic form, receives little benefit from three dimensional (3D) rendering. This paper presents a series of 3D graphical notations demonstrating effective use of the third dimension in modelling. This is done by e.g., connecting several graphs together, or in using the Z co-ordinate to show special kinds of edges. Each notation combines several familiar 2D diagrams, which can be reproduced from 2D projections of the 3D model. 3D models are useful even in the absence of a powerful graphical workstation: even 2D stereoscopic projections can expose more information than a plain planar diagram

Using the event calculus for tracking the normative state of contracts

In this work, we have been principally concerned with the representation of contracts so that their normative state may be tracked in an automated fashion over their deployment lifetime. The normative state of a contract, at a particular time, is the aggregation of instances of normative relations that hold between contract parties at that time, plus the current values of contract variables. The effects of contract events on the normative state of a contract are specified using an XML formalisation of the Event Calculus, called ecXML. We use an example mail service agreement from the domain of web services to ground the discussion of our work. We give a characterisation of the agreement according to the normative concepts of: obligation, power and permission, and show how the ecXML representation may be used to track the state of the agreement, according to a narrative of contract events. We also give a description of a state tracking architecture, and a contract deployment tool, both of which have been implemented in the course of our work.

Teaching Object-Oriented Modelling using Concept Maps

As one of the most important tasks in object-oriented analysis and design (OOAD) is the abstraction of the problem domain into specific concepts or objects, information technology (IT) students need appropriate skills of abstraction in order to identify the essential concepts and relationships within a problem domain. However students in higher education generally find difficulty performing abstractions of real-world problems within the context of OOAD. Concept mapping is a popular tool used in education for facilitating learning, comprehension and the development of knowledge structures. We have successfully adopted concept maps as stepping-stones to assist students in constructing class and sequence diagrams. In this paper, we present a framework for teaching object-oriented (OO) modelling using concept maps. This framework – comprising four teaching modules – could be integrated into existing OOAD courses at the undergraduate or postgraduate level, and OOAD workshops to help software engineering educators resolve some of the difficulties they face in trying to teach OOAD. We also report results of an evaluative study on the effectiveness of integrating concept mapping techniques into an introductory OOAD course

Object-Oriented Refinement and Proof using Behaviour Functions

This paper proposes a new calculus for expressing the behaviour of object-oriented systems. The semantics of the calculus is given in terms of operators from computational category theory. The calculus aims to span the gulf between abstract specification and concrete implementation of object-oriented systems using mathematically verifiable properties and transformations. The calculus is compositional and can be used to express the behaviour of partial system views. The calculus is used to specify, analyse and refine a simple case study

Object-oriented refinement and proof using behaviour functions.

This paper proposes a new calculus for expressing the behaviour of object-oriented systems. The semantics of the calculus is given in terms of operators from computational category theory. The calculus aims to span the gulf between abstract specification and concrete implementation of object-oriented systems using mathematically verifiable properties and transformations. The calculus is compositional and can be used to express the behaviour of partial system views. The calculus is used to specify, analyse and refine a simple case study

Institutional Arrangements: A Gate Towards Sustainable Land Use

Various common problems can be observed of the ongoing land management processes in Central and Eastern European (CEE) countries. The problems appear mainly because of conflicting legislation, performance of procedures, political unwillingness, lack of capacity of the local municipalities and other public administration, insufficiency of information and people participation, lack of skills of the professionals and in public administration. Source of all the mentioned problems is insufficient understanding of the institutional setting of the land management processes. The aim of this contribution is to introduce the reader to the theory of the institutional economics and discuss its importance for systematisation of both the regulatory framework, i.e. institutions – ‘rules of the game’ and the procedures in the fields of territorial planning and real property formation. This theory provides a vocabulary to describe the balance between the regulatory structures (public sector) and the market forces (private sector) that will allow controlled growth and will be perceived as of general economic and social well being to the populace. Thus, the paper is intended to activate and urge politicians, governmental authorities, non-governmental organizations, academic staff and managers of private firms. This contribution also can be seen as a source for further development of concepts for analysis of the observed problems. Hence combining the theory with appropriate methodology may suggest, how to deal with the stated various problems. Monographic descriptive method and logical analysis have been used in this contribution