A frame signature matrix for analysing and comparing interaction design behaviour

Protocol studies are an established method to investigate design behaviour. In the context of a project to investigate novice interaction design (ID) behaviour across protocols and cultures, we found that existing design behaviour analysis frameworks did not provide reliable results. This paper describes the development of a new approach to analyse and compare ID behaviour using verbal protocols. We augment Schön’s basic design and reflection cycle with construction of a frame signature matrix and analogical categorisation coding. We demonstrate this approach by comparing two protocols of novice interaction designers in Botswana. The initial findings indicate that this approach increases consistency and accuracy of coding, and that there are different degrees of reframing for the design problem and solutions

Co-evolving problems and solutions: The case of novice interaction designers in Botswana and the UK

This paper establishes that problem-solution co-evolution is observed in novice interaction designers in the UK and Botswana. However, in the majority of Botswana protocols we could see a new type of co-evolution, which we termed solution-problem co-evolution. Solution- problem co-evolution uses ‘off the shelf’’ solutions to structure the problem space. Both types of co-evolution are described and discussed in this paper. The findings are drawn from the analysis of 18 (5 UK, 13 Botswana) 1-hour design protocols from two cohorts of students studying the same undergraduate Open University Interaction Design module, one in Botswana and one in the UK. Participants were required to complete a medical interaction design task under controlled conditions. We based our analysis on a coding scheme that was developed specifically for this protocol study. The coding scheme is based on Schön’s seminal work on reflective practice. It visually represents activities in the problem and solutions spaces

A protocol study of novice interaction design behaviour in Botswana: solution-driven interaction design

Think aloud studies and protocol analysis are well-known in the field of HCI, but most often these studies focus on usability evaluations, or on the use of technology. Rarely are they used to investigate the behaviour of interaction designers. In this paper, we report on a protocol study with novice interaction designers in Botswana. Participants had just completed the design section of an undergraduate module on Interaction Design that actively promotes a problem-driven approach to the design of interactive products, yet the participants behaved in a way that is closer to a solution-driven approach. The module emphasizes user-centred design, prototyping methods to support design development, and evaluating design detail. Yet participants suggest solutions before exploring the context of use, use prototyping methods to capture, rather than to develop, designs, and do not produce detailed designs. In a problem-solving context, some of these behaviours are typical of novices, but in a design context they are also seen in experienced designers. The results presented here reveal the detail of the approach adopted by these students, and contribute to the wider debate concerning the internationalization of HCI education

Tribological and vibro-acoustic behaviour of a lubricated contact subjected to the stick-slip phenomenon: the case of the spring-brake system

The main objective of the PhD thesis is the analysis of stick-slip phenomena in lubricated contacts, by merging the physical, experimental and numerical points of view and proposing a novel methodological approach, applied here to an industrial case. Nowadays, in the field of applied mechanics and tribology, one of the most important challenges is the ability to predict and reduce surface damages, failure of machine components and undesirable frictional and dynamic characteristics. In particular, the appearance of friction-induced vibrations at the contact is hardly controllable and can result in high local contact pressure, elevated stresses, system oscillations, discontinuous motion and premature failure]. Understanding the conditions for which the system is more predisposed to the stick-slip phenomenon may allow preventing the appearance of such instabilities, and the related vibrations and noise emission. Friction-Induced Vibrations are a phenomenon that engages multiple scientific challenges, due to the complexity of their physics. Focusing the attention on stick-slip phenomena, these are generally characterized by a saw-tooth displacement-time evolution. Each change in the contact parameters influences directly the dynamic and frictional response of the system, due to the mutual influence of the local scale (contact) and the system scale (macroscopic frictional and vibrational response). Moreover, the presence of a lubricant, and in particular of grease, at the contact interface, increases the complexity of the phenomenon, from both a tribological and dynamic point of view. Lubricated systems are supposed to reduce the frictional losses and wear, but they can also collaborate in the appearance of dynamic contact instabilities, due to the friction-velocity characteristics when passing from boundary to mixed contact regimes. The complex rheology of a grease, function of both the matrix, additive and oil responses, becomes then a key point for the occurrence and evolution of stick-slip. Despite the great importance of this phenomenon, from both scientific and industrial points of view, a lack emerges into the literature about stick-slip of lubricated interfaces. The few works are manly focused on molecular dynamics simulations and numerical modelling of the dynamical response of the system. The different role of the grease components, during the sliding, is nowadays still not clear. Nevertheless, the complex rheology of a grease, function of both the thickener, the base oil and the additives, is a key point for understanding and controlling the occurrence and evolution of stick-slip. Moreover, a general approach is needed to account for the coupling between the local phenomena (e.g. lubricated contact response) and the system dynamic response. Aiming to improve the understanding of stick-slip in lubricated contacts, the present Ph.D. work proposes a novel methodological approach to the stick-slip problem of a lubricated contact, referring to a real industrial case, in order to deploy the obtained results in a more realistic and detailed manner. The subject of the investigation is a mechanical brake used in tubular electric actuators, which can present frictional instabilities originated at the lubricated contact between the two main brake components. The methodology used is twofold: i) on one hand, experimental tests are carried out to understand the local frictional response of the lubricated contact; ii) on the other hand, a lumped model is created in order to simulate and analyse the system dynamic response. Introducing the information about the local lubricated contact behaviour (friction law), achieved experimentally, into the numerical model, it is possible to investigate the parameters for which the system is more predisposed to the stick-slip phenomenon and recreate a representative scenario of its appearance. Particular attention has been placed on the analysis of the lubricant rheology, dealing with different types of lubricants and regimes of lubrication, with both oils and greases. The frictional response has been thus related to the different contributions of the grease components (i.e. thickener, base oil and additives) on the rheology at the interface. The obtained local information has been then integrated in the lumped model to evaluate the unstable dynamic response of the entire system (i.e. the stick-slip phenomena) and identify the lubrication parameters that most influence its appearance. The numerical analysis had the dual objective of understanding the role of the local contact response in the system instability and investigating the stick-slip occurrence as a function of the key system parameters. The obtained results allowed to identify the lubrication components, and the respective friction-velocity curves, more favourable for the stick-slip occurrence. Combining the grease rheology evolutions with the stick-slip dynamic response represents a further challenge in both the domains of research. The Ph.D. thesis has been developed in collaboration between the Sapienza University of Rome, Department of Mechanical and Aerospace Engineering (Rome, Italy), the Institut National des Sciences Appliquées (INSA) of Lyon, laboratory LaMCoS (Lyon, France), and the company SOMFY S.A. (Cluses, France)

Framing behaviours in novice interaction designers

Some recent findings with expert designers relate problem-solution co-evolution and analogy use to framing practices. We wanted to understand if novices also use coevolution and analogies to frame their thinking. Furthermore we wanted to see if there are any differences across cultures. The paper reports an analysis of data gained from protocol studies with novice interaction designers in the UK and Botswana. Novice interaction designers in the UK and Botswana show some similarities in framing behaviours using co-evolution and opening analogies to develop metaphorical themes in framing. But within these observations we also found differences across the cohorts. The implications are discussed in the light of adopting appropriate design pedagogy for novices in different cultures

Investigating the topology of interacting networks - Theory and application to coupled climate subnetworks

Network theory provides various tools for investigating the structural or functional topology of many complex systems found in nature, technology and society. Nevertheless, it has recently been realised that a considerable number of systems of interest should be treated, more appropriately, as interacting networks or networks of networks. Here we introduce a novel graph-theoretical framework for studying the interaction structure between subnetworks embedded within a complex network of networks. This framework allows us to quantify the structural role of single vertices or whole subnetworks with respect to the interaction of a pair of subnetworks on local, mesoscopic and global topological scales. Climate networks have recently been shown to be a powerful tool for the analysis of climatological data. Applying the general framework for studying interacting networks, we introduce coupled climate subnetworks to represent and investigate the topology of statistical relationships between the fields of distinct climatological variables. Using coupled climate subnetworks to investigate the terrestrial atmosphere's three-dimensional geopotential height field uncovers known as well as interesting novel features of the atmosphere's vertical stratification and general circulation. Specifically, the new measure "cross-betweenness" identifies regions which are particularly important for mediating vertical wind field interactions. The promising results obtained by following the coupled climate subnetwork approach present a first step towards an improved understanding of the Earth system and its complex interacting components from a network perspective

Acoustic sequences in non-human animals: a tutorial review and prospectus.

Animal acoustic communication often takes the form of complex sequences, made up of multiple distinct acoustic units. Apart from the well-known example of birdsong, other animals such as insects, amphibians, and mammals (including bats, rodents, primates, and cetaceans) also generate complex acoustic sequences. Occasionally, such as with birdsong, the adaptive role of these sequences seems clear (e.g. mate attraction and territorial defence). More often however, researchers have only begun to characterise - let alone understand - the significance and meaning of acoustic sequences. Hypotheses abound, but there is little agreement as to how sequences should be defined and analysed. Our review aims to outline suitable methods for testing these hypotheses, and to describe the major limitations to our current and near-future knowledge on questions of acoustic sequences. This review and prospectus is the result of a collaborative effort between 43 scientists from the fields of animal behaviour, ecology and evolution, signal processing, machine learning, quantitative linguistics, and information theory, who gathered for a 2013 workshop entitled, 'Analysing vocal sequences in animals'. Our goal is to present not just a review of the state of the art, but to propose a methodological framework that summarises what we suggest are the best practices for research in this field, across taxa and across disciplines. We also provide a tutorial-style introduction to some of the most promising algorithmic approaches for analysing sequences. We divide our review into three sections: identifying the distinct units of an acoustic sequence, describing the different ways that information can be contained within a sequence, and analysing the structure of that sequence. Each of these sections is further subdivided to address the key questions and approaches in that area. We propose a uniform, systematic, and comprehensive approach to studying sequences, with the goal of clarifying research terms used in different fields, and facilitating collaboration and comparative studies. Allowing greater interdisciplinary collaboration will facilitate the investigation of many important questions in the evolution of communication and sociality.This review was developed at an investigative workshop, “Analyzing Animal Vocal Communication Sequences” that took place on October 21–23 2013 in Knoxville, Tennessee, sponsored by the National Institute for Mathematical and Biological Synthesis (NIMBioS). NIMBioS is an Institute sponsored by the National Science Foundation, the U.S. Department of Homeland Security, and the U.S. Department of Agriculture through NSF Awards #EF-0832858 and #DBI-1300426, with additional support from The University of Tennessee, Knoxville. In addition to the authors, Vincent Janik participated in the workshop. D.T.B.’s research is currently supported by NSF DEB-1119660. M.A.B.’s research is currently supported by NSF IOS-0842759 and NIH R01DC009582. M.A.R.’s research is supported by ONR N0001411IP20086 and NOPP (ONR/BOEM) N00014-11-1-0697. S.L.DeR.’s research is supported by the U.S. Office of Naval Research. R.F.-i-C.’s research was supported by the grant BASMATI (TIN2011-27479-C04-03) from the Spanish Ministry of Science and Innovation. E.C.G.’s research is currently supported by a National Research Council postdoctoral fellowship. E.E.V.’s research is supported by CONACYT, Mexico, award number I010/214/2012.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1111/brv.1216

Comparing multiple simulators using Bayesian emulators

Bayesian emulation has proved to be a useful tool for working with complicated, high dimensional simulators, approximating the simulator's behaviour in a probabilistic way, enabling operations such as prediction or calibration, and therefore providing an ecient approximation to the simulator's representation of the system. Complex systems, however, are often modelled by several different simulators, each with dierent strengths and weaknesses. Combining them to better understand the system, or comparing their behaviour as functions, is very dicult. This is largely because their input spaces cannot be directly linked. In this thesis, we present two methods for using emulation to jointly model two simulators, allowing them to be compared. We also introduce two simulators of the ocean carbon cycle, OG99NPZD and HadOCC. The ocean carbon cycle is of interest largely because it concerns the biological processes by which some carbon is stored in the deep ocean. These simulators have dierent input spaces and model the system dierently, and standard emulation proves to be unable to compare them. The first method for two simulators, hierarchical emulation, works with pairs of simulators for which one is an extension of the other, and therefore whose input spaces are mostly similar. This uses the relationship between the simulators to emulate the more complex as a sum of the simpler simulator and some newly created functions. Validation studies using hierarchical emulators to model two versions of HadOCC show that the hierarchical emulator outperforms the standard methods in modelling both the extended simulator and the dierence between the two. The second, intermediate variable emulation, makes no constraint on the relationship between the simulators, instead making connections using sub-processes represented in both. This allows the representations of a system by two simulators to be directly compared; the contributions of the dierent sub-processes can be contrasted, and the sub-processes themselves can be used to gain better understanding of the relationship between the two input spaces. Intermediate variable emulators are used to compare OG99NPZD and HadOCC. Finally, to enable an ecient and robust implementation of these methods, as well as of the standard emulation method, an object-oriented framework for emulation is presented

Vibratory response of stator cores of large induction motors operating in an offshore installation.

The work presented in this thesis is based on theoretical and experimental investigations into the vibration behaviour of stator assemblies of induction motors. The aim is to evaluate the effectiveness of using the Finite Element Method to predict the natural frequencies, mode shapes and vibratory response of a large induction motor stator on an offshore installation. This information of stator vibration behaviour is a prerequisite for the installation of a reliable vibration monitoring strategy to detect motor faults. Initial studies are based on the analysis of a small (11 KW) motor stator under free and mounted conditions so that a realistic mathematical representation of a motor stator can be verified by comparing calculated with measured dynamic characteristics. The next stage of the project was to design and develop an original test rig which was a scaled down model of a large (2 MW) induction motor stator assembly. A combined theoretical and experimental investigation of large motor stator dynamic behaviour was carried out and calculated results from a finite element analysis were compared with laboratory measurements. The finite element models were then developed to include response calculations and the vibration amplitudes due to a simple external forcing function and the fundamental electromagnetic radial forcing function were calculated. Measured response levels were recorded on the frame and core of the test rig for comparison. Finally an experimental investigation was carried out into the effects of a single-phasing fault on the vibration signal measured on the core and frame of the large stator assembly model. The main conclusion drawn from this study is that the Finite Element Method is an effective approximation technique for calculating the vibratory response information necessary for reliable motor fault detection by stator assembly vibration monitoring