User-made immobilities: a transitions perspective

In this paper we aim to conceptualize the role of users in creating, expanding and stabilizing the automobility system. Drawing on transition studies we offer a typology of user roles including user-producers, user-legitimators, user-intermediaries, user-citizens and user-consumers, and explore it on the historical transition to the automobile regime in the USA. We find that users play an important role during the entire transition process, but some roles are more salient than others in particular phases. Another finding is that the success of the transition depends on the stabilization of the emerging regime that will trigger upscaling in terms of the numbers of adopters. The findings are used to reflect on potential crossovers between transitions and mobilities research

Manifest domains:analysis and description

Abstract We show that manifest domains, an understanding of which are a prerequisite for software requirements prescriptions, can be precisely described: narrated and formalised. We show that such manifest domains can be understood as a collection of endurant, that is, basically spatial entities: parts, components and materials, and perdurant, that is, basically temporal entities: actions, events and behaviours. We show that parts can be modeled in terms of external qualities whether: atomic or composite parts, having internal qualities: unique identifications, mereologies, which model relations between parts, and attributes. We show that the manifest domain analysis endeavour can be supported by a calculus of manifest domain analysis prompts: is_entity, is_endurant, is_perdurant, is_part, is_component, is_material, is_atomic, is_composite, has_components, has_materials, has_concrete_type, attribute_names, is_stationary, etcetera; and show how the manifest domain description endeavour can be supported by a calculus of manifest domain description prompts: observe_part_sorts, observe_part_type, observe_components, observe_materials, observe_unique_identifier, observe_mereology, observe_attributes. We show how to model attributes, essentially following Michael Jackson (Software requirements &amp; specifications: a lexicon of practice, principles and prejudices. ACM Press, Addison-Wesley, Reading, 1995 ), but with a twist: The attribute model introduces the attribute analysis prompts is_static_attribute, is_dynamic_attribute, is_inert_attribute, is_reactive_attribute, is_active_attribute, is_autonomous_attribute, is_biddable_attribute and is_programmable_attribute. The twist suggests ways of modeling “access” to the values of these kinds of attributes: the static attributes by simply “copying” them, once, the reactive and programmable attributes by “carrying” them as function parameters whose values are kept always updated, and the remaining, the external_attributes, by inquiring, when needed, as to their value, as if they were always offered on CSP-like channels (Hoare, Communicating sequential processes. C.A.R. Hoare series in computer science. Prentice-Hall International, London, 2004 ). We show how to model essential aspects of perdurants in terms of their signatures based on the concepts of endurants. And we show how one can “compile” descriptions of endurant parts into descriptions of perdurant behaviours. We do not show prompt calculi for perdurants. The above contributions express a method with principles, techniques and tools for constructing domain descriptions. It is important to realise that we do not wish to nor claim that the method can describe all that it is interesting to know about domains. </jats:p

Reuse of safety certification artefacts across standards and domains: A systematic approach

Reuse of systems and subsystem is a common practice in safety-critical systems engineering. Reuse can improve system development and assurance, and there are recommendations on reuse for some domains. Cross-domain reuse, in which a previously certified product typically needs to be assessed against different safety standards, has however received little attention. No guidance exists for this reuse scenario despite its relevance in industry, thus practitioners need new means to tackle it. This paper aims to fill this gap by presenting a systematic approach for reuse of safety certification artefacts across standards and domains. The approach is based on the analysis of the similarities and on the specification of maps between standards. These maps are used to determine the safety certification artefacts that can be reused from one domain to another and reuse consequences. The approach has been validated with practitioners in a case study on the reuse of an execution platform from railway to avionics. The results show that the approach can be effectively applied and that it can reduce the cost of safety certification across standards and domains. Therefore, the approach is a promising way of making cross-domain reuse more cost-effective in industry.European Commission's FP7 programm

Identifying the emerging vulnerability of railway transport systems across countries by automated analysis of railway accident reports

Although railway accident reports and recommendations are proposed after railway accidents, practitioners and researchers suffer from the need to deal with a large amount of textual data given that most railway safety-related information is recorded and stored in the form of text. Hence, there is a growing need for accurate estimations of the vulnerability of railway transport and for effective mitigation strategies. This thesis extends knowledge on the vulnerability of the railway system by exploring the underlying hazards and building rigorous and automated models to enlarge the database. The conceptual frameworks HazardMap and RecoMap were developed to overcome this gap, using Natural Language Processing (NLP) topic models for the automated analysis of textual data to extract critical insights. Empirical data was retrieved from official railway accident reports published by four countries: Australia - the Australian Transport Safety Bureau (ATSB), the UK - Rail Accident Investigation Branch (RAIB), the US - National Transportation Safety Board (NTSB) and Canada - the Transportation Safety Board of Canada (TSB). Scoping workshops and a survey were conducted to evaluate the usefulness and consistency of railway practice. Case studies of the application to the risk at level crossings and the platform–train interface risks are provided to illustrate how the models proposed work with real-world data. The interpretation of findings indicates the potentially emerging hazard of deterioration in railway safety. Potential barriers to learning across jurisdictions and time might deteriorate the organisational safety culture and endanger railway. To address such obstacles, the HazardMap and RecoMap proposed are capable of automating hazard analysis with adequate accuracy to help stakeholders better understand hazards and help practitioners learn across jurisdictions and time

Street recovery in the age of COVID-19: Simultaneous design for mobility, customer traffic and physical distancing

This paper explores the relationship between urban traffic, retail location and disease control during the COVID-19 pandemic crisis and tries to find a way to simultaneously address these issues for the purpose of street recovery. Drawing on the concept of the 15 min city, the study also aims at seeking COVID-19 exit paths and next-normal operating models to support long-term business prosperity using a case study of Royal Street, East Perth in Western Australia. Nearly half of the shops became vacant or closed at the end of 2020 along the east section of Royal Street, demonstrating the fragility of small business in a car-oriented street milieu that is inadequately supported by proper physical, digital and social infrastructure. A key finding from the analysis is the formulation of the concept of the Minute City. This describes a truly proximity-centred and socially driven hyper-local city, where residents and retailers work together on the local street as a walkable public open space (other than movement space), and benefit from ameliorated traffic flow, improved business location and a safer, connected community