6,952 research outputs found

    “Samhandling”: On the nuances of resilience through case study research in emergency response operations

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    Standard emergency-management procedures offer guidance on how organizations can improve their handling of all types of emergencies. However, such a generalization undermines uncertainties and oversimplifies the complexity of real work practices during an emergency response operation (ERO). The handling of the COVID-19 pandemic highlights how uncertainty and escalating consequences reinforce the need for resilience in EROs. To illustrate the key elements of our suggested approach and its practical implications, we discuss the issues in light of a case study related to a COVID-19 outbreak on a floating oil rig in the North Sea. The analysis reveals several instances of creative problem solving, and individual and collective efforts beyond the scope of the standard procedures. It also underlines how the shortcomings of resource allocation and over-planning might lead to inflexibility, thus harming EROs' efficiency. Our analysis highlights that the key to resilient EROs lies in robust coordination, the ability to improvise, transparency, and trusting communication between the actors involved. Greater focus on network building—proactively maintained through regular training and exercise activities—strengthens resilience in emergency-management systems. All these traits link to the Norwegian term “samhandling,” a notion which is here proposed to summarize and connect these resilience capacities

    Additional application of the NASCAP code. Volume 1: NASCAP extension

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    The NASCAP computer program comprehensively analyzes problems of spacecraft charging. Using a fully three dimensional approach, it can accurately predict spacecraft potentials under a variety of conditions. Several changes were made to NASCAP, and a new code, NASCAP/LEO, was developed. In addition, detailed studies of several spacecraft-environmental interactions and of the SCATHA spacecraft were performed. The NASCAP/LEO program handles situations of relatively short Debye length encountered by large space structures or by any satellite in low earth orbit (LEO)

    Additional application of the NASCAP code. Volume 2: SEPS, ion thruster neutralization and electrostatic antenna model

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    The interactions of spacecraft systems with the surrounding plasma environment were studied analytically for three cases of current interest: calculating the impact of spacecraft generated plasmas on the main power system of a baseline solar electric propulsion stage (SEPS), modeling the physics of the neutralization of an ion thruster beam by a plasma bridge, and examining the physical and electrical effects of orbital ambient plasmas on the operation of an electrostatically controlled membrane mirror. In order to perform these studies, the NASA charging analyzer program (NASCAP) was used as well as several other computer models and analytical estimates. The main result of the SEPS study was to show how charge exchange ion expansion can create a conducting channel between the thrusters and the solar arrays. A fluid-like model was able to predict plasma potentials and temperatures measured near the main beam of an ion thruster and in the vicinity of a hollow cathode neutralizer. Power losses due to plasma currents were shown to be substantial for several proposed electrostatic antenna designs

    Electron-, Mu-, and Tau-Number Conservation in a Supernova Core

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    We study if the neutrino mixing parameters suggested by the atmospheric neutrino anomaly imply chemical equilibrium between mu- and tau-flavored leptons in a supernova (SN) core. The initial flavor-conversion rate would indeed be fast if the nu_mu-nu_tau-mixing angle were not suppressed by second-order refractive effects. The neutrino diffusion coefficients are different for nu_mu, anti-nu_mu, nu_tau and anti-nu_tau so that neutrino transport will create a net mu and tau lepton number density. This will typically lead to a situation where the usual first-order refractive effects dominate, further suppressing the rate of flavor conversion. Altogether, neutrino refraction has the nontrivial consequence of guaranteeing the separate conservation of e, mu, and tau lepton number in a SN core on the infall and cooling time scales, even when neutrino mixing angles are large.Comment: Slightly expanded version with improved presentation, no changes of substanc

    MATE. Multi Aircraft Training Environment

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    Analysis of the charging of the SCATHA (P78-2) satellite

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    The charging of a large object in polar Earth orbit was investigated in order to obtain a preliminary indication of the response of the shuttle orbiter to such an environment. Two NASCAP (NASA Charging Analyzer Program) models of SCATHA (Satellite Charging at High Altitudes) were used in simulations of charging events. The properties of the satellite's constituent materials were compiled and representations of the experimentally observed plasma spectra were constructed. Actual charging events, as well as those using test environments, were simulated. Numerical models for the simulation of particle emitters and detectors were used to analyze the operation of these devices onboard SCATHA. The effect of highly charged surface regions on the charging conductivity within a photosheath was used to interpret results from the onboard electric field experiment. Shadowing calculations were carried out for the satellite and a table of effective illuminated areas was compiled

    Uncorking the potential of wine language for young wine tourists

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    Effective communication with consumers underpins growth in wine knowledge that, in turn, contributes to growth in wine consumption. Indeed, tasting notes may enhance consumers’ experiences of wine. Yet wine language is full of fuzzy concepts. In this chapter, we consider the language used to talk about wine, specifically the humanlike features of wine (e.g., wine is described as honest, sexy, shy, or brooding). We demonstrate that metaphoric language is integral to the experience of wine and influences consumer behaviour. We discuss practical implications for the cellar door experience, and for effective and ethical wine communication. We conclude that metaphoric language is a pedagogical and cultural platform for engaging younger wine tourists in the cellar door experience, which is a significant revenue source for micro, small, and medium wineries

    The Concept of Culture in Critical Mathematics Education

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    © Springer International Publishing AG, part of Springer Nature 2018. This is a post-peer-review, pre-copyedit version of a chapter published in The Philosophy of Mathematics Education Today. The final authenticated version is available online at: http://dx.doi.org/10.1007/978-3-319-77760-3A well-known critique in the research literature of critical mathematics education suggests that framing educational questions in cultural terms can encourage ethnic-cultural essentialism, obscure conflicts within cultures and promote an ethnographic or anthropological stance towards learners. Nevertheless, we believe that some of the obstacles to learning mathematics are cultural. ‘Stereotype threat’, for example, has a basis in culture. Consequently, the aims of critical mathematics education cannot be seriously pursued without including a cultural approach in educational research. We argue that an adequate conception of culture is available and should include normative/descriptive and material/ideal dyads as dialectical moments

    New constraints on neutrino physics from Boomerang data

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    We have performed a likelihood analysis of the recent data on the Cosmic Microwave Background Radiation (CMBR) anisotropy taken by the Boomerang experiment. We find that this data places a strong upper bound on the radiation density present at recombination. Expressed in terms of the equivalent number of neutrino species the 2σ2\sigma bound is N_nu < 13, and the standard model prediction, N_nu = 3.04, is completely consistent the the data. This bound is complementary to the one found from Big Bang nucleosynthesis considerations in that it applies to any type of radiation, i.e. it is not flavour sensitive. It also applies to the universe at a much later epoch, and as such places severe limits on scenarios with decaying neutrinos. The bound also yields a firm upper limit on the lepton asymmetry in the universe.Comment: 4 pages, 2 postscript figures, matches version to appear in PR

    Estimating seasonal abundance of a central place forager using counts and telemetry data

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    R.J.S. was supported by a Natural Environment Research Council studentship.Obtaining population estimates of species that are not easily observed directly can be problematic. However, central place foragers can often be observed some of the time, e.g. when seals are hauled out. In these instances, population estimates can be derived from counts, combined with information on the proportion of time that animals can be observed. We present a modelling framework to estimate seasonal absolute abundance using counts and information from satellite telemetry data. The method was tested on a harbour seal population in an area of southeast Scotland. Counts were made monthly, between November 2001 and June 2003, when seals were hauled out on land and were corrected for the proportion of time the seals were at sea using satellite telemetry. Harbour seals (n=25) were tagged with satellite relay data loggers between November 2001 and March 2003. To estimate the proportion of time spent hauled out, time at sea on foraging trips was modelled separately from haul-out behaviour close to haul-out sites because of the different factors affecting these processes. A generalised linear mixed model framework was developed to capture the longitudinal nature of the data and the repeated measures across individuals. Despite seasonal variability in the number of seals counted at haul-out sites, the model generated estimates of abundance, with an overall mean of 846 (95% CI: 767 to 979). The methodology shows the value of using count and telemetry data collected concurrently for estimating absolute abundance, information that is essential to assess interactions between predators, fish stocks and fisheries.Publisher PDFPeer reviewe
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