4,025 research outputs found

    Fratricide: defective decision making

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    Motivation – to explore the applicability of a Human Factors methodology for the investigation of fratricide. Research approach – The EAST methodology was used to analyse an incident of fratricide and its ability to explore the Famous Five of Fratricide (F3) model was investigated. Findings/Design – the analysis revealed that EAST was able to provide explicit discussion of the Famous Five of Fratricide (F3) models five causal factors of communication, cooperation, coordination, schemata and situation awareness. Research limitations/Implications – the research explored a single case study and as such is couched at the initial phases of investigation. Originality/Value – the analysis provides a contribution to the knowledge urrounding fratricide both with respect to the novel application of the EAST methodology to an incident of fratricide, and also the causal factors identified by EAST within the fratricide incident. Take away message – the EAST methodology provides an innovative way of exploring causality in incidents of fratricide<br/

    Phase space shifts in command structures in networked systems

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    This paper presents the rationale behind an important enhancement to the NATO SAS-050 approach space, combined with empirical results which take advantage of these enhancements. In Part 1 a new theoretical legacy for the NATO model is presented. This legacy inspires a number of developments which allow live data to be plotted into it, and we demonstrate that the model is well able to discriminate between alternative C2 structures. Part 2 illustrates this feature with multinational data from the ELICIT community. It is surprising to see that teams in both C2 and Edge conditions operate in broadly the same area of the phase space cube. The structure of the pre-ordained ELICIT ‘classic C2’ hierarchy and the deterministic nature of the shared task are put forward as explanations for this, and as future enhancements to the ELICIT paradigm

    Servitisation and value co-production in the UK music industry

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    Since the rise of music on the internet, record companies have reported falling sales of physical products. This has occurred at a time when technology has radically increased choice, availability and the opportunity for the consumer to purchase music. As the music industry has moved from a product to a service business model, has the loss of sales meant they have not taken their customers with them? This paper provides a description of different music consumers based upon quantitative analysis of consumer characteristics. The paper then undertakes an exploration of the relationship between the consumer groups and their purchasing preference in relation to intangible ‘service’ purchase such as downloaded music and the purchase of a tangible physical product such as CDs or vinyl. In addition, we analyse the relationship between consumer types and their propensity to actively engage with music communities, such as through engagement with social media, and thus their willingness to coproduce greater value. Finally we explore the moderating effects of age and time devoted to listening to music on purchasing preferences and music discovery

    Effect of lubricant ageing on lubricants' physical and chemical properties and tribological performance; Part I: effect of lubricant chemistry

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    Purpose Ageing has been known to affect the performance of lubricants. However, there is a lot of debate as to whether ageing is beneficial or detrimental to the wear performance of lubricants. Design/methodology/approach The purpose of this research is to evaluate the effect of ageing on the viscosity, total acid number and Fourier-transform infrared spectroscopy information of a series of lubricants. The tribological performance (friction and wear) of the aged lubricants is also studied, followed by X-ray photoelectron spectroscopy analysis on the selected post-test samples to study the tribochemical features of the tribofilm. Findings The results show that ageing has a different impact on lubricants and tribological performances based on the physical and chemical properties. Originality/value These findings will be compared with the research on the role of water in lubricant ageing (Part II of this study)

    Effect of base oil polarity on the micropitting behaviour in rolling-sliding contacts

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    An automated micropitting test rig that uses the proven three-point contact configuration was applied to study the effect of base oil polarity on micropitting behaviour in rolling-sliding contacts. The tribological tests using one polar (ester) and one non-polar (polyalpha olefin [PAO]) base oil mixed with four different additives were first done in a micropitting rig to study the friction, wear, and micropitting performance. The tested specimen after tribological tests were examined by an optical microscope to study the micropitting on the surface. The X-ray photoelectron spectroscopy (XPS) was applied to obtain the related tribochemical information from the reaction layer. The results showed that higher wear and less micropits formed when testing with ester-based lubricants. This was related to the higher affinity to the steel surface of polar base oil molecules that can compete with additives to attach to the surface, resulting in a thinner reaction layer and shorter chain phosphates

    Combining social network analysis and the NATO Approach Space to define agility. Topic 2: networks and networking

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    This paper takes the NATO SAS-050 Approach Space, a widely accepted model of command and control, and gives each of its primary axes a quantitative measure using social network analysis. This means that the actual point in the approach space adopted by real-life command and control organizations can be plotted along with the way in which that point varies over time and function. Part 1 of the paper presents the rationale behind this innovation and how it was subject to verification using theoretical data. Part 2 shows how the enhanced approach space was put to use in the context of a large scale military command post exercise. Agility is represented by the number of distinct areas in the approach space that the organization was able to occupy and there was a marked disparity between where the organization thought it should be and where it actually was, furthermore, agility varied across function. The humans in this particular scenario bestowed upon the organization the levels of agility that were observed, thus the findings are properly considered from a socio-technical perspective

    Plane waves in quantum gravity: breakdown of the classical spacetime

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    Starting with the Hamiltonian formulation for spacetimes with two commuting spacelike Killing vectors, we construct a midisuperspace model for linearly polarized plane waves in vacuum gravity. This model has no constraints and its degrees of freedom can be interpreted as an infinite and continuous set of annihilation and creation like variables. We also consider a simplified version of the model, in which the number of modes is restricted to a discrete set. In both cases, the quantization is achieved by introducing a Fock representation. We find regularized operators to represent the metric and discuss whether the coherent states of the quantum theory are peaked around classical spacetimes. It is shown that, although the expectation value of the metric on Killing orbits coincides with a classical solution, its relative fluctuations become significant when one approaches a region where null geodesics are focused. In that region, the spacetimes described by coherent states fail to admit an approximate classical description. This result applies as well to the vacuum of the theory.Comment: 11 pages, no figures, version accepted for publication in Phys. Rev.

    A human factors approach to analysing military command and control

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    This paper applies the Event Analysis for Systemic Teamwork (EAST) method to an example of military command and control. EAST offers a way to describe system level 'emergent properties' that arise from the complex interactions of system components (human and technical). These are described using an integrated methods approach and modelled using Task, Social and Knowledge networks. The current article is divided into three parts: a brief description of the military command and control context, a brief description of the EAST method, and a more in depth presentation of the analysis outcomes. Numerous findings emerge from the application of the method. These findings are compared with similar analyses undertaken in civilian domains, where Network Enabled Capability (NEC) is already in place. The emergent properties of the military scenario relate to the degree of system reconfigurability, systems level Situational Awareness (SA), team-working and the role of mediating technology. It is argued that the EAST method can be used to offer several interesting perspectives on designing and specifying NEC capability in military context
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