191 resultados para CLOSURES


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S'estudia la resposta de la capa de barreja oceànica al forçament atmosfèric considerant dades obtingudes durant 12 dies d'abril del 2001 a 42 estacions a través de l'Atlàntic nord seguint aproximadament la latitud de 53ºN. Aquestes dades inclouen, a més de variables atmosfèriques, mesures de CTD, velocitats amb ADCP i dades de microestructura obtingudes amb un perfilador de caiguda lliure. En aquest últim cas, s'han desenvolupat tècniques de processament de les dades que també es presenten aquí. El transsecte estudiat segueix la posició climatològica del rotacional mitjà anual del vent igual a zero i travessa el corrent del Labrador i algunes branques i meandres del Corrent Atlàntic Nord. El forçament atmosfèric es va caracteritzar per vents intensos i fluxos superficials de calor negatius, tot i que, tal com es dedueix de la comparació del gruix de la capa de barreja amb la longitud de Monin-Obukov, la barreja induïda pel vent va dominar sobre la convectiva durant tot el transsecte.

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Most parameterizations for precipitating convection in use today are bulk schemes, in which an ensemble of cumulus elements with different properties is modelled as a single, representative entraining-detraining plume. We review the underpinning mathematical model for such parameterizations, in particular by comparing it with spectral models in which elements are not combined into the representative plume. The chief merit of a bulk model is that the representative plume can be described by an equation set with the same structure as that which describes each element in a spectral model. The equivalence relies on an ansatz for detrained condensate introduced by Yanai et al. (1973) and on a simplified microphysics. There are also conceptual differences in the closure of bulk and spectral parameterizations. In particular, we show that the convective quasi-equilibrium closure of Arakawa and Schubert (1974) for spectral parameterizations cannot be carried over to a bulk parameterization in a straightforward way. Quasi-equilibrium of the cloud work function assumes a timescale separation between a slow forcing process and a rapid convective response. But, for the natural bulk analogue to the cloud-work function (the dilute CAPE), the relevant forcing is characterised by a different timescale, and so its quasi-equilibrium entails a different physical constraint. Closures of bulk parameterization that use the non-entraining parcel value of CAPE do not suffer from this timescale issue. However, the Yanai et al. (1973) ansatz must be invoked as a necessary ingredient of those closures.

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Examination of conditional instability of the second kind (CISK) and wind-induced surface heat exchange (WISHE), two proposed mechanisms for tropical cyclone and polar low intensification, suggests that the sensitivity of the intensification rate of these disturbances to surface properties, such as surface friction and moisture supply, will be different for the two mechanisms. These sensitivities were examined by perturbing the surface characteristics in a numerical model with explicit convection. The intensification rate was found to have a strong positive dependence on the heat and moisture transfer coefficients, while remaining largely insensitive to the frictional drag coefficient. CISK does not predict the observed dependence of vortex intensification rate on the heat and moisture transfer coefficients, nor the insensitivity to the frictional drag coefficient since it anticipates that intensification rate is controlled by frictional convergence in the boundary layer. Since neither conditional instability nor boundary moisture content showed any significant sensitivity to the transfer coefficients, this is true of CISK using both the convective closures of Ooyama and of Charney and Eliassen. In comparison, the WISHE intensification mechanism does predict the observed increase in intensification rate with heat and moisture transfer coefficients, while not anticipating a direct influence from surface friction.

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Expanding national services sectors and global competition aggravate current and perceived future market pressures on traditional manufacturing industries. These perceptions of change have provoked a growing intensification of geo-political discourses on technological innovation and ‘learning’, and calls for competency in design among other professional skills. However, these political discourses on innovation and learning have paralleled public concerns with the apparent ‘growth pains’ from factory closures and subsequent increases in unemployment, and its debilitating social and economic implications for local and regional development. In this respect the following investigation sets out to conceptualize change through the complementary and differing perceptions of industry and regional actors’ experiences or narratives, linking these perceptions to their structure-determined spheres of agent-environment interactivity. It aims to determine whether agents’ differing perceptions of industry transformation can have a role in the legitimization of their interests in, and in sustaining their organizational influence over the process of industry-regional transformation. It argues that industry and regional agent perceptions are among the cognitive aspects of agent-environment interactivity that permeate agency. It stresses agents’ ability to reason and manipulate their work environments to preserve their self-regulating interests in, and task representative influence over the multi-jurisdictional space of industry-regional transformation. The contributions of this investigation suggest that agents’ varied perceptions of industry and regional change inform or compete for influence over the redirection of regional, industry and business strategies. This claim offers a greater appreciation for the reflexive and complex institutional dimensions of industry planning and development, and the political responsibility to socially just forms of regional development. It positions the outcomes of this investigation at the nexus of intensifying geo-political discourses on the efficiency and equity of territorial development in Europe.

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A continuum model describing sea ice as a layer of granulated thick ice, consisting of many rigid, brittle floes, intersected by long and narrow regions of thinner ice, known as leads, is developed. We consider the evolution of mesoscale leads, formed under extension, whose lengths span many floes, so that the surrounding ice is treated as a granular plastic. The leads are sufficiently small with respect to basin scales of sea ice deformation that they may be modelled using a continuum approach. The model includes evolution equations for the orientational distribution of leads, their thickness and width expressed through second-rank tensors and terms requiring closures. The closing assumptions are constructed for the case of negligibly small lead ice thickness and the canonical deformation types of pure and simple shear, pure divergence and pure convergence. We present a new continuum-scale sea ice rheology that depends upon the isotropic, material rheology of sea ice, the orientational distribution of lead properties and the thick ice thickness. A new model of lead and thick ice interaction is presented that successfully describes a number of effects: (i) because of its brittle nature, thick ice does not thin under extension and (ii) the consideration of the thick sea ice as a granular material determines finite lead opening under pure shear, when granular dilation is unimportant.

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We develop the essential ingredients of a new, continuum and anisotropic model of sea-ice dynamics designed for eventual use in climate simulation. These ingredients are a constitutive law for sea-ice stress, relating stress to the material properties of sea ice and to internal variables describing the sea-ice state, and equations describing the evolution of these variables. The sea-ice cover is treated as a densely flawed two-dimensional continuum consisting of a uniform field of thick ice that is uniformly permeated with narrow linear regions of thinner ice called leads. Lead orientation, thickness and width distributions are described by second-rank tensor internal variables: the structure, thickness and width tensors, whose dynamics are governed by corresponding evolution equations accounting for processes such as new lead generation and rotation as the ice cover deforms. These evolution equations contain contractions of higher-order tensor expressions that require closures. We develop a sea-ice stress constitutive law that relates sea-ice stress to the structure tensor, thickness tensor and strain rate. For the special case of empty leads (containing no ice), linear closures are adopted and we present calculations for simple shear, convergence and divergence.

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The effect of the tensor component of the Skyrme effective nucleon-nucleon interaction on the single-particle structure in superheavy elements is studied. A selection of the available Skyrme forces has been chosen and their predictions for the proton and neutron shell closures investigated. The inclusion of the tensor term with realistic coupling strength parameters leads to a small increase in the spin-orbit splitting between the proton 2f7/2 and 2f5/2 partners, opening the Z=114 shell gap over a wide range of nuclei. The Z=126 shell gap, predicted by these models in the absence of the tensor term, is found to be stongly dependent on neutron number with a Z=138 gap opening for large neutron numbers, having a consequent implication for the synthesis of neutron-rich superheavy elements. The predicted neutron shell structures remain largely unchanged by inclusion of the tensor component.

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A generalization of Arakawa and Schubert's convective quasi-equilibrium principle is presented for a closure formulation of mass-flux convection parameterization. The original principle is based on the budget of the cloud work function. This principle is generalized by considering the budget for a vertical integral of an arbitrary convection-related quantity. The closure formulation includes Arakawa and Schubert's quasi-equilibrium, as well as both CAPE and moisture closures as special cases. The formulation also includes new possibilities for considering vertical integrals that are dependent on convective-scale variables, such as the moisture within convection. The generalized convective quasi-equilibrium is defined by a balance between large-scale forcing and convective response for a given vertically-integrated quantity. The latter takes the form of a convolution of a kernel matrix and a mass-flux spectrum, as in the original convective quasi-equilibrium. The kernel reduces to a scalar when either a bulk formulation is adopted, or only large-scale variables are considered within the vertical integral. Various physical implications of the generalized closure are discussed. These include the possibility that precipitation might be considered as a potentially-significant contribution to the large-scale forcing. Two dicta are proposed as guiding physical principles for the specifying a suitable vertically-integrated quantity.

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Simple first-order closure remains an attractive way of formulating equations for complex canopy flows when the aim is to find analytic or simple numerical solutions to illustrate fundamental physical processes. Nevertheless, the limitations of such closures must be understood if the resulting models are to illuminate rather than mislead. We propose five conditions that first-order closures must satisfy then test two widely used closures against them. The first is the eddy diffusivity based on a mixing length. We discuss the origins of this approach, its use in simple canopy flows and extensions to more complex flows. We find that it satisfies most of the conditions and, because the reasons for its failures are well understood, it is a reliable methodology. The second is the velocity-squared closure that relates shear stress to the square of mean velocity. Again we discuss the origins of this closure and show that it is based on incorrect physical principles and fails to satisfy any of the five conditions in complex canopy flows; consequently its use can lead to actively misleading conclusions.

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Purpose – The textiles, clothing, and footwear (TCF) industry has struggled in Australia since the government commenced dismantling tariffs. By sourcing from Asia, middlemen undercut established suppliers, and retail chains set benchmark low prices with their imported “house” labels. The policy-makers predicted that local producers would become more efficient, and export to make up for lost sales, but the media paints a picture of rising imports, retrenchments, and factory closures. The research objective was to discover what strategies the survivors (actually) employ in adapting to the pressures of globalisation.

Design/methodology/approach – More than 30 companies were involved in the study, ranging from small family businesses to subsidiaries of big multinationals. Each case study was based on an interview with a senior executive, normally followed by a plant tour. This methodology suits a fresh topic, as it avoids preconceptions and imposes no bounds.

Findings – Results show that the policy change was based on “pie in the sky” forecasts. Increasingly, TCF production is transferred to cheap offshore locations, generally via subcontracting plus the “badging” of foreign designs. To survive, local factories should focus on quality and customer service, preferably in niche markets (like uniforms), or for specific customer groups, and develop technologically advanced products. A move down the supply chain into retailing can also assist. Large multinational corporations that engage in foreign direct investment dominate the management literature.

Originality/value – This paper presents a different perspective, neglected in international operations management, whereby domestically oriented businesses attempt to defend themselves against the adverse consequences of globalisation.

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Euripides’ Medea has been reinvented several times in the twentieth century. While some modern Medeas reiterate conservative tropes of the monstrous feminine or the evil of the cultural Other, the infanticidal figure of Medea is also open to more politically progressive usages. Indeed, several modern versions of Medea are overt in their politicisation of the problems of colonialism and/or institutionalised gender dissymmetry: the Medeas of Pier Paolo Pasolini, Heiner Müller, Christa Wolf, and more recently the indigenous Australian version by Wesley Enoch, for example, enact resistance to the interpretative closures that construct Medea as a caricature of the evil Other. But what lends the Euripidean narrative to such politicisations? And what role does the infanticide have in modern politicisations of the narrative?

To answer these questions, the paper examines Pier Paolo Pasolini’s 1969 film Medea from his Trilogy of Life series. Focussing on Pasolini’s representation of Medea’s signature act, maternal infanticide, the paper outlines the complex ways in which this motif is integral to the film’s contestation of imperialist ideologies, values and practices, and its affiliations with Marxist and feminist criticism. Drawing upon theories of subjectivity and postcolonial discourse, the paper argues that the infanticide motif is politically enabling precisely because it exalts the politics of the ways in which subjectivity is defined. That is, the apparent blessing of the sun god over Medea’s murderous act speaks to the ways in which subjectivity is formed by the symbolic order: a point recalling Medea’s earlier articulation that society systematically demonises and oppresses foreigners and women. The films representation of infanticide, then, can be read in the light of the narratives politicisation of the discourses that define subjectivity and the hegemonic practices that subjugate and dominate the subaltern. So, while Medea’s infanticide is sometimes dismissed as a demonising representation of the cultural and sexual Other, it can also be read as the key to understanding Medea’s political radicality, drawing attention to the discourses of rights-bearing subjectivity in both its ancient and modern incarnations.

Pasolini’s project of anti-colonialism, however, is fraught with certain paradoxes. To politicise the predicament of imperial subjugation, Pasolini’s Medea places the burden of authenticity on the cultural and sexual Other, on Medea - and on Medea’s culture of origin, Colchis. In this way, Pasolini’s Medea mobilises the problematic discourses of ‘First World’ modernity that define the ‘Third World’ as the carrier of the symbolic burden of authenticity as well as of ‘the sacred.’ Pasolini’s Medea thus offers an overly schematic and abstract representation of the relationship between coloniser and colonised. However, Pasolini’s Medea is not simply or finally a reification of these discourses; rather it strategically mobilises them – just as it strategically mobilises the monstrous act of infanticide – to make its political point.

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The outbreak of the Influenza A (H1N1) virus has led to numerous precautionary school closures in several countries. No research is available on the school teachers’ perceptions as a health protective resource in controlling communicable disease outbreaks. The purposes of this study were to examine the risk perception, the perceived understanding of preventive measures and contingency plans, and the needs of school teachers before the imminent outbreak of H1N1. This survey was conducted with 1,169 Hong Kong school teachers before school closures due to the H1N1 outbreak. The results showed that the teachers were well aware of H1N1 but were still worried about the spread of H1N1 infection. The teachers’ worries depended on their psychological reaction, the adequacy of the control measures, government support in providing infectious disease knowledge, perceived understanding of preventive measures and contingency plans, students and parents’ awareness, and the need for support from health professionals.

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The toppling of Saddam Hussein in 2003 saw Iraq's media sector shift from a handful of state-run media outlets that served as propaganda machines, to a vast array of Iraqi-owned newspapers, radio stations and television channels which are being fervently produced and avidly consumed nationally. Not unexpectedly, several problems have accompanied this divergent, ad-hoc and highly volatile mediascape. Although recognizing important factors, including dangers faced by Iraqi journalists, and the dearth of appropriate press laws, this article focuses instead on attempts by certain key foreign and domestic political bodies to manufacture consent in Iraq via their interference in the post-Saddam media sector. These foreign influences are Iran, Saudi Arabia and the United States, each of which funds, controls and manipulates different Iraqi media outlets. Not surprisingly, the United States has been the most active in this respect, utilizing both overt and clandestine propaganda techniques as well as forced closures to control the Iraqi media sector. Unfortunately, measures such as these are not limited to foreign governments: both the Iraqi government and the Kurdish Regional Government have used similar means to control and silence Iraq's nascent public sphere. The article concludes by noting the irony of limited press freedom in Iraq during this crucial phase of its transition from despotism to democracy.

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Objective: The aim of the present study was to examine the impact of Pandemic (H1N1) 2009 Influenza on the Australian emergency nursing and medicine workforce, specifically absenteeism and deployment.

Methods: Data were collected using an online survey of 618 members of the three professional emergency medicine or emergency nursing colleges.

Results: Despite significant increases in emergency demand during the Pandemic (H1N1) 2009 Influenza, 56.6% of emergency nursing and medicine staff reported absenteeism of at least 1 day and only 8.5% of staff were redeployed. Staff illness with influenza-like illness was reported by 37% of respondents, and 87% of respondents who became ill were not tested for the Pandemic (H1N1) 2009 Influenza. Of the respondents who became ill, 43% (n = 79) reported missing no days of work and only 8% of respondents (n = 14) reported being absent for more than 5 days. The mean number of days away from work was 3.73 (standard deviation = 3.63). Factors anecdotally associated with staff absenteeism (caregiver responsibilities, concern about personal illness, concern about exposing family members to illness, school closures, risk of quarantine, stress and increased workload) appeared to be of little or no relevance. Redeployment was reported by 8% of respondents and the majority of redeployment was for operational reasons.

Conclusion: Future research related to absenteeism, redeployment during actual pandemic events is urgently needed. Workforce data collection should be an integral part of organizational pandemic planning.

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This chapter explores the possible ontological questions and epistemological propositions that arise from detailed empirical research into cinema closures. Repeated pronouncements of the ‘Death of Cinema’ in the wake of technological, social and industrial change serve to reinforce the coincidence of ‘death’ with a type of ‘closure’. The evocation of a ‘crisis’ in the cinema is ordinarily articulated within the terms of specific cultural concerns around transience and transformation in the social experience of the cinema. However, rather than adding another chapter to the apocalyptic historiography of the cinema this paper proposes instead the constitutive importance of ‘closure’ as a critical tool for rethinking our defining assumptions about cinema(s). Specifically, the chapter will demonstrate how the conceptual granularity entailed in the development of a detailed database of venue openings and closings (the Cinema and Audiences in Australia Project database) can in turn lead to a fundamental reconsideration of the ontology of the cinema itself.