Property-Based Testing - The ProTest Project

The ProTest project is an FP7 STREP on property based testing. The purpose of the project is to develop software engineering approaches to improve reliability of service-oriented networks; support fault-finding and diagnosis based on specified properties of the system. And to do so we will build automated tools that will generate and run tests, monitor execution at run-time, and log events for analysis. The Erlang / Open Telecom Platform has been chosen as our initial implementation vehicle due to its robustness and reliability within the telecoms sector. It is noted for its success in the ATM telecoms switches by Ericsson, one of the project partners, as well as for multiple other uses such as in facebook, yahoo etc. In this paper we provide an overview of the project goals, as well as detailing initial progress in developing property based testing techniques and tools for the concurrent functional programming language Erlang

Well-definedness of Streams by Transformation and Termination

Streams are infinite sequences over a given data type. A stream specification is a set of equations intended to define a stream. We propose a transformation from such a stream specification to a term rewriting system (TRS) in such a way that termination of the resulting TRS implies that the stream specification is well-defined, that is, admits a unique solution. As a consequence, proving well-definedness of several interesting stream specifications can be done fully automatically using present powerful tools for proving TRS termination. In order to increase the power of this approach, we investigate transformations that preserve semantics and well-definedness. We give examples for which the above mentioned technique applies for the ransformed specification while it fails for the original one

Troubled waters: an institutional analysis of ageing Dutch and American waterway infrastructure

Waterways are one of the oldest systems for the transportation of cargo and continue to play a vital role in the economies of some countries. Due to societal change, climate change and the ageing of assets, the conditions influencing the effective functioning of these systems seem to be changing. These changing conditions require measures to renew, adapt or renovate these waterway systems. However, measures with the sole aim of improving navigation conditions have encountered resistance, as the general public, and stakeholders in particular, value these waters in many more ways than navigation alone. Therefore, a more inclusive, integrated approach is required, rather than a sectoral one. Addressing these contemporary challenges requires a shift in the traditional waterway authorities' regimes. The aim of this study is to identify elements in the institutional setting where obstacles and opportunities for a more inclusive approach can be found. Two major waterway systems, the American and the Dutch, have been analyzed using the Institutional Analysis and Development framework to reveal those obstacles and opportunities. The results show that horizontal coordination and a low pay-off for an inclusive approach is particularly problematic. The American case also reveals a promising aspect – mandatory local co-funding for federal navigation projects acts as a stimulus for broad stakeholder involvement. Improving horizontal coordination and seizing opportunities for multifunctional development can open pathways to optimize the value of waterway systems for society

Книжковий фонд Відділу стародруків та рідкісних видань Національної бібліотеки України імені В.І. Вернадського як джерельна база історичних досліджень

This paper is a "statement" for the March special issue of JEAPM on "Impact Assessment Research: Achievements, Gaps and Future Directions"

Co-creating value through renewing waterway networks: a transaction-cost perspective

Since modern waterway networks are increasingly confronted with ageing assets, waterway renewal will increase in importance for western countries. Renewal can be regarded an impetus for realising integrated waterway networks that internalise externalities, which entails broad stakeholder involvement. This can be coordinated through different inter-organisational structures. Applying a transaction-cost perspective, we contribute to the assessment of effective governance arrangements for renewing waterway networks in such an integrated fashion. Our aim is to examine efficient inter-organisational structures for waterway renewal, as perceived by actors involved in a case study of the Dutch waterways. Our findings show that waterway renewal incorporates additional functionalities in terms of capacity (expansion or reduction), but not so much in terms of quality (combining transportation aims with spatial objectives such as ecology or regional development). Inter-organisational structures that address geographical interrelatedness and, hence, broader stakeholder involvement were associated with uncertain and time-consuming transactions, because of extensive negotiations regarding the alignment of conflicting interests and the crossing of geographical and administrative boundaries. Also, a change in interdependency from hierarchical towards contractual relationships was required, putting dominant actors (the national government) in an unfamiliar position in which they loosen their grip on infrastructure investments. Perceptions on transactions centre on sectoral aims and individual assets, whereas the actual transaction may be different if a perspective is taken that includes the greater waterway system, the wider spatial surroundings and a longer-term horizon. We conclude that short-term, transportation objectives overrule longer-term, integrative objectives, which withholds strategic considerations required for aligning waterway interests

Guided Unfoldings for Finding Loops in Standard Term Rewriting

In this paper, we reconsider the unfolding-based technique that we have introduced previously for detecting loops in standard term rewriting. We improve it by guiding the unfolding process, using distinguished positions in the rewrite rules. This results in a depth-first computation of the unfoldings, whereas the original technique was breadth-first. We have implemented this new approach in our tool NTI and compared it to the previous one on a bunch of rewrite systems. The results we get are promising (better times, more successful proofs).Comment: Pre-proceedings paper presented at the 28th International Symposium on Logic-Based Program Synthesis and Transformation (LOPSTR 2018), Frankfurt am Main, Germany, 4-6 September 2018 (arXiv:1808.03326

Planning for waterway renewal: balancing institutional reproduction and institutional change

Modern waterway networks are ageing and need to be renewed, yet the institutional context in the waterway sector is averse to change because of path dependencies. Waterway renewal, therefore, requires actors to navigate between institutional reproduction (exploiting current practices) and change (exploring new practices). Using a case study of institutions in the Dutch national waterways, we mainly find instances of institutional reproduction, which turns waterway renewal into a technical and financial exercise. However, institutional change becomes increasingly evident through a new functional-relational path, suggesting that planning for waterway renewal also entails reconsidering novel waterway configurations and incorporating neighbouring spatial developments