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Simulation is a key tool for researching complex system behaviour. Agent-based simulation has been applied across domains, such as biology, health, economics and urban sciences. However, engineering robust, efficient, maintainable, and reliable agent-based simulations is challenging. We present a vision for engineering agent simulations comprising a family of domain-specific modelling languages (DSMLs) that integrates core software engineering, validation and simulation experimentation. We relate the vision to examples of principled simulation, to show how the DSMLs would improve robustness, efficiency, and maintainability of simulations. Focusing on how to demonstrate the fitness for purpose of a simulator, the envisaged approach supports bi-directional transparency and traceability between the original domain understanding to the implementation, interpretation of results and evaluation of hypotheses. [ABSTRACT FROM AUTHOR]

In May 2019, a workshop on principled development of future agent-based simulations was held at Keele University. Participants spanned companies and academia, and a range of domains of interest, as well as participant career stages. This report summarizes the discussions and main outcomes from this workshop. [ABSTRACT FROM AUTHOR]

Images of hydrocarbon extraction at sea remain strikingly circumscribed. The most extensively circulated are either the work of professional industrial photographers employed by oil companies to take carefully vetted promotional shots, or of news photographers commissioned to document catastrophes. Corporate-sponsored photography enforces the massive scale of offshore rigs, their technological sophistication, and apparent ability to withstand the vicissitudes of the ocean; it also tends to imply that companies adhere to strict safety regimens, and equal opportunity hiring practices. Photographs created by offshore oil workers are not widely circulated in the public domain. However, three collections of images recently donated to Newfoundland and Labrador's provincial archives offer new viewpoints on the oil industry. Lance Butler, David Boutcher, and Lloyd Major were all employed on the Ocean Ranger platform, which capsized off the coast of Newfoundland in 1982 with the loss of 84 lives–including Boutcher's. The men's images resituate, expand upon, and on occasions challenge tropes that predominate in corporate photography; the striking arrangement of David Boutcher's snapshots in album format by his mother is also salutary. This essay argues for the necessity of "onshoring" the offshore, and claims that workers' photographs can potentially help us do so through a variety of means. [ABSTRACT FROM AUTHOR]

Modelling and simulation of complex systems can create scientific research tools that allow the inaccessible dynamic aspects of systems to be explored in ways that are not possible in live systems. In some scientific contexts, there is a need to be able to create and use such simulations to explore and generate hypotheses alongside conventional laboratory research. The principled complex systems modelling and simulation (CoSMoS) approach was created to support these activities, as a response to a perceived gap in the software engineering development process for simulation. The article presents some of the software engineering motivation for CoSMoS, by exploring this perceived gap. Following from this analysis, the article considers the validation of complex systems simulators, especially where these are to be used in ongoing research. [ABSTRACT FROM AUTHOR]

A collaboration between cancer biologists and academic software engineers has been exploring the development of an agent-based simulator to inform and support work on the dynamics of cell proliferation in the study of prostate disorders. The research has influenced and been informed by the CoSMoS project. This paper presents the simulation project (which is not yet complete). We reflect on the reality of following CoSMoS principles; we describe the domain exploration and show how software modelling approaches (here, Petri nets, state diagrams) can be used to express both biological and software models. We explore fitness for purpose and consider ways to present a fitness argument. We consider issues in choosing simulation media and mapping from domain models through to code. The implementation emphasis is on traceability to support reuse and extension of the simulator, as well as demonstrable fitness for purpose. Initial work on calibration is presented. We discuss the calibration results, that both support and challenge the design and assumptions captured in the domain modelling and development activities. [ABSTRACT FROM AUTHOR]

The article examines two Romanticist paintings created for Indigenous audiences in the British colonies of Tasmania and Newfoundland. The paintings discussed are "Governor Arthur's Proclamation to the Tasmanian Peoples, 1830" by George Frankland and a lost, untitled painting by Amelia Curran. It is suggested that the paintings are examples of what the author calls alternative Romanticisms, which adapt global cultural forms for local purposes. Particular focus is given to the implications of the artists' acknowledgment of Indigenous presence in these colonies. Topics discussed include Aboriginal Australian peoples, the Beothuk people in Newfoundland, art as a means of communication, and symmetry.

A literary criticism of the book "Cloud of Bone" by Bernice Morgan is presented. It examines the long succession of texts and the emblematic supposed disappearance of indigenous people from Newfoundland. It explores the epigraph of the book. It also examines how the author uses her characters unambiguously to favor memory over history.

The article compares figurations of the Canadian island of Newfoundland with those of the Australian island of Tasmania through close analysis of two significant contemporary novels. It argues that E. Annie Proulx's "The Shipping News" and Richard Flanagan's "Death of a River Guide" construct Newfoundland and Tasmania as havens from the disorienting effects of postmodernism.

The article looks at how annotated drawings, created by Newfoundland indigenous woman Shanawdithit and ethnologist William Epps Cormack, have been interpreted. It recounts Shanawdithit's time among the white settlers of Newfoundland, and tells of her fondness for creating images using Indigenous and European techniques. It states that these drawings are useful because they show the value in different methods of representation and understanding.

A metamodel has been defined as: a model of a model; a definition of a language; a description of abstract syntax; and a description of a domain. Because of these varied definitions, it is difficult to explain why metamodels are constructed, what can be done with them, and how they are built. This tutorial introduces the key concepts, terminology and philosophy behind metamodelling, focusing on its use for language engineering , and expressed in a way that is intended to be accessible to researchers who may be more familiar with the use of traditional context-free grammar techniques. We highlight the main differences between metamodelling and grammar-based approaches, describe how to map metamodelling concepts and techniques to grammar concepts and techniques, and highlight some of the strengths and weaknesses of metamodelling via a set of small, but realistic examples. [ABSTRACT FROM AUTHOR]

A metamodel has been defined as: a model of a model; a definition of a language; a description of abstract syntax; and a description of a domain. Because of these varied definitions, it is difficult to explain why metamodels are constructed, what can be done with them, and how they are built. This tutorial introduces the key concepts, terminology and philosophy behind metamodelling, focusing on its use for language engineering , and expressed in a way that is intended to be accessible to researchers who may be more familiar with the use of traditional context-free grammar techniques. We highlight the main differences between metamodelling and grammar-based approaches, describe how to map metamodelling concepts and techniques to grammar concepts and techniques, and highlight some of the strengths and weaknesses of metamodelling via a set of small, but realistic examples. [ABSTRACT FROM AUTHOR]

Simulations of evolutionary dynamics often employ white noise as a model of stochastic environmental variation. Whilst white noise has the advantages of being simply generated and analytically tractable, empirical analyses demonstrate that most real environmental time series have power spectral densities consistent with pink or red noise, in which lower frequencies contribute proportionally greater amplitudes than higher frequencies. Simulated white noise environments may therefore fail to capture key components of real environmental time series, leading to erroneous results. To explore the effects of different noise colours on evolving populations, a simple evolutionary model of the interaction between life-history and the specialism-generalism axis was developed. Simulations were conducted using a range of noise colours as the environments to which agents adapted. Results demonstrate complex interactions between noise colour, reproductive rate, and the degree of evolved generalism; importantly, contradictory conclusions arise from simulations using white as opposed to red noise, suggesting that noise colour plays a fundamental role in generating adaptive responses. These results are discussed in the context of previous research on evolutionary responses to fluctuating environments, and it is suggested that Artificial Life as a field should embrace a wider spectrum of coloured noise models to ensure that results are truly representative of environmental and evolutionary dynamics. [ABSTRACT FROM AUTHOR]

Model-driven engineering introduces additional challenges for controlling and managing software evolution. Today, tools exist for generating model editors and for managing models with transformation, validation, merging and weaving. There is limited support, however, for model migration-a development activity in which instance models are updated in response to metamodel evolution. In this paper, we propose conservative copy-a style of model transformation that we believe is well-suited to model migration-and Epsilon Flock-a compact model-to-model transformation language tailored for model migration. The proposed structures are evaluated by comparing the conciseness of model migration strategies written in different styles of transformation language, using several examples of evolution taken from UML and the graphical modelling framework. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) consist of multiple, distributed nodes each with limited resources. With their strict resource constraints and application-specific characteristics, WSNs contain many challenging tradeoffs. This paper proposes a bioinspired load balancing approach, based on pheromone signalling mechanisms, to solve the tradeoff between service availability and energy consumption. We explore the performance consequences of the pheromone-based load balancing approach using (1) a system-level simulator, (2) deployment of real sensor testbeds to provide a competitive analysis of these evaluation methodologies. The effectiveness of the proposed algorithm is evaluated with different scenario parameters and the required performance evaluation techniques are investigated on case studies based on sound sensors. [ABSTRACT FROM AUTHOR]