The emergence of Systems of Systems (SoSs) and Systems of Systems Engineering (SoSE) is largely driven by global societal needs including energy-water-food nexus, population demographics, global climate, integrated transport, security and social activity. However, due to their scale, structural and functional complexity and emergent properties, these global spanning Cyber-Physical Systems of Systems are becoming increasingly complex and more difficult for current requirements engineering (RE) practices to handle. In this paper, we firstly introduce SoSE as an emerging discipline and key characteristics of SoSs. We then highlight the challenges that the RE discipline must respond to. We discuss some weaknesses of current RE techniques and approaches to cope with the complexity of SoSs. We then argue that there is a need for the global RE community to evolve current RE approaches and to develop new ways of thinking, new RE capabilities and possibly a new RE science as a key mechanism for addressing requirements engineering complexities posed by Systems of Systems. We then outline a requirements engineering perspective and research agenda that identifies 'top-10' research themes informed by a cluster of four Systems of Systems Engineering projects funded by the European Commission's Horizon 2020 research programme.

Users' feedback is vital to improve software quality and it provides developers with a rich knowledge on how software meets users' requirements in practice. Feedback informs how software should adapt, or be adapted, at runtime and what evolutionary actions to take in the next release. However, studies have noted that accommodating the different preferences of users on how feedback should be requested is a complex task and requires a careful engineering process. This calls for an adaptive feedback acquisition mechanisms to cater for such variability. In this paper, we tackle this problem by employing the concept of Persona to aid software engineers understand the various users' behaviours and improve their ability to design feedback acquisition techniques more efficiently. We create a set of personas based on a mixture of qualitative and quantitative studies and propose PAFA, a Persona-based method for Adaptive Feedback Acquisition.

Users' feedback is a main source of knowledge on how users perceive the role of software in meeting their requirements. Collectively, such feedback helps shaping software autonomous and semi-autonomous adaptation decisions of what is called Social Adaptation. It also helps developers to identify loci in the system where an evolution should be introduced in the next release. Despite this role of users' feedback, there is a lack of systematic engineering approaches on how to design its acquisition mechanisms. In this paper, we observe that the acquisition of feedback should be itself adaptive to the context of use. We conduct an empirical study following a mixed-method sequential exploratory approach to explore the main drivers of such adaptation and understand users' attitude when being asked to provide feedback. Our findings are meant to enrich the knowledge base for developers and researchers in users-centric, or crowd-centric, adaptation. It also highlights areas of study for a future research in the area.

Due to an increasingly connected society and industry, our modern societal world and all industry sectors now increasingly depend on large-scale complex Systems of Systems (SoS). The emerging interdisciplinary area of SoS and Systems of Systems Engineering (SoSE) is largely driven by societal needs including public services such as health, transport, water, energy, food security, etc. The scale, complexities and challenges presented by SoS require us to go beyond traditional Requirements Engineering (RE) approaches. However, as is evident from publications in major Requirements Engineering conferences and journals, no significant effort has been expedited towards addressing specific RE issues for Systems of Systems Engineering. This panel explores key RE challenges in Systems of Systems Engineering, specifically, the areas in which the international RE community need to focus its research, and the approaches that are most likely to meet these challenges effectively. We first introduce Systems of Systems Engineering and outline key characteristics of SoS. We conclude by arguing that there is an urgent need for the global RE community to develop new ways of thinking, new capabilities and possibly a new science as a key mechanism for addressing requirements complexities posed by Systems of Systems.

The large-scale Systems of Systems (SoS) are there to improve the provision of societal services. These are driven by global drivers such as population growth, aging, food security, energy security and climate change. However, a considerable number of SoS projects resulted in failures, causing detrimental economic impact. This paper presents a set of preliminary results from an European Commission (EC) funded project called T-AREA-SoS (Trans-Atlantic Research and Education Agenda on Systems of Systems). The primary purpose of T-AREA-SoS is to provide input to EC's 80 billion Horizon 2020 research programme in formulating a Strategic Research Agenda for Systems of Systems Engineering (SoSE) that spans American and European activities. An initial set of prioritised SoSE research elements derived from an online survey are discussed from an economic and societal stance using examples from heterogeneous sectors such as transport, energy and manufacturing.

Requirements engineering is a creative process in which stakeholders work together to create ideas for new software systems that are eventually expressed as requirements. This paper reports a workshop that integrated creativity techniques with different types of use case and system context modeling to discover stakeholder requirements for EASM, a future air space management software system to enable the more effective, longer-term planning of UK and European airspace use. The workshop was successful in that it provided a range of outputs that were later assessed for their novelty and usefulness in the final specification of the EASM software. The paper describes the workshop structure, gives examples of outputs from it, and uses these results to answer 2 research questions about the utility of creativity techniques and workshops that had not been answered in previous research.

This scientific evaluation paper investigates the effectiveness of different scenario forms and uses on requirements discovery. Lt reports results from the application of scenario tools during the specification of requirements on socio-technical systems to improve the environmental impact of aircraft operations at a regional UK airport. Stakeholders walked through scenarios in both text and visual simulation form, and discovered requirements during workshops and whilst observing actors in their workplace. Results revealed both qualitative and quantitative differences in discovered requirements that have potential implications for models of scenario-based requirements discovery and the design of scenario tools.

This paper proposes a new process to address the lack of guidance for acquiring requirements to enable evaluation of commercial off-the-shelf (COTS) software. The process is part goal-driven and part context-driven, in that it exploits models of the candidate COTS software as well as process goals to guide a requirements engineering team. The paper demonstrates the approach with selection of a commercial electronic mail system. It also describes a prototype software tool currently under development, and outlines future research directions to extend and evaluate the approach.