895 resultados para 090108 Satellite Space Vehicle and Missile Design and Testing
Resumo:
This paper describes the design, implementation and testing of an intelligent knowledge-based supervisory control (IKBSC) system for a hot rolling mill process. A novel architecture is used to integrate an expert system with an existing supervisory control system and a new optimization methodology for scheduling the soaking pits in which the material is heated prior to rolling. The resulting IKBSC system was applied to an aluminium hot rolling mill process to improve the shape quality of low-gauge plate and to optimise the use of the soaking pits to reduce energy consumption. The results from the trials demonstrate the advantages to be gained from the IKBSC system that integrates knowledge contained within data, plant and human resources with existing model-based systems. (c) 2005 Elsevier Ltd. All rights reserved.
Resumo:
To achieve CO2 emissions reductions the UK Building Regulations require developers of new residential buildings to calculate expected CO2 emissions arising from their energy consumption using a methodology such as Standard Assessment Procedure (SAP 2005) or, more recently SAP 2009. SAP encompasses all domestic heat consumption and a limited proportion of the electricity consumption. However, these calculations are rarely verified with real energy consumption and related CO2 emissions. This paper presents the results of an analysis based on weekly head demand data for more than 200 individual flats. The data is collected from recently built residential development connected to a district heating network. A methodology for separating out the domestic hot water use (DHW) and space heating demand (SH) has been developed and compares measured values to the demand calculated using SAP 2005 and 2009 methodologies. The analysis shows also the variance in DHW and SH consumption between both size of the flats and tenure (privately owned or housing association). Evaluation of the space heating consumption includes also an estimation of the heating degree day (HDD) base temperature for each block of flats and its comparison to the average base temperature calculated using the SAP 2005 methodology.
Resumo:
The global atmospheric electric circuit is driven by thunderstorms and electrified rain/shower clouds and is also influenced by energetic charged particles from space. The global circuit maintains the ionosphere as an equipotential at∼+250 kV with respect to the good conducting Earth (both land and oceans). Its “load” is the fair weather atmosphere and semi-fair weather atmosphere at large distances from the disturbed weather “generator” regions. The main solar-terrestrial (or space weather) influence on the global circuit arises from spatially and temporally varying fluxes of galactic cosmic rays (GCRs) and energetic electrons precipitating from the magnetosphere. All components of the circuit exhibit much variability in both space and time. Global circuit variations between solar maximum and solar minimum are considered together with Forbush decrease and solar flare effects. The variability in ion concentration and vertical current flow are considered in terms of radiative effects in the troposphere, through infra-red absorption, and cloud effects, in particular possible cloud microphysical effects from charging at layer cloud edges. The paper identifies future research areas in relation to Task Group 4 of the Climate and Weather of the Sun-Earth System (CAWSES-II) programme.
Resumo:
This paper considers the dynamics of deposition around and across the causewayed enclosure at Etton, Cambridgeshire. As a result of detailed re-analysis (particularly refitting) of the pottery and flint assemblages from the site, it proved possible to shed new light both on the temporality of occupation and the character of deposition there. Certain aspects of our work challenge previous interpretations of the site, and of causewayed enclosures in general; but, just as importantly, others confirm materially what has previously been suggested. The quantities of material deposited at Etton reveal that the enclosure was occupied only very intermittently and certainly less regularly than other contemporary sites in the region. The spatial distribution of material suggests that the enclosure ditch lay open for the entirety of the monument's life, but that acts of deposition generally focused on a specific part of the monument at any one time. As well as enhancing our knowledge of one particular causewayed enclosure, it is hoped that this paper – in combination with our earlier analysis of the pit site at Kilverstone – makes clear the potential that detailed material analysis has to offer in relation to our understanding of the temporality of occupation on prehistoric sites in general.
Resumo:
The impact on the dynamics of the stratosphere of three approaches to geoengineering by solar radiation management is investigated using idealized simulations of a global climate model. The approaches are geoengineering with sulfate aerosols, titania aerosols, and reduction in total solar irradiance (representing mirrors placed in space). If it were possible to use stratospheric aerosols to counterbalance the surface warming produced by a quadrupling of atmospheric carbon dioxide concentrations, tropical lower stratospheric radiative heating would drive a thermal wind response which would intensify the stratospheric polar vortices. In the Northern Hemisphere this intensification results in strong dynamical cooling of the polar stratosphere. Northern Hemisphere stratospheric sudden warming events become rare (one and two in 65 years for sulfate and titania, respectively). The intensification of the polar vortices results in a poleward shift of the tropospheric midlatitude jets in winter. The aerosol radiative heating enhances the tropical upwelling in the lower stratosphere, influencing the strength of the Brewer-Dobson circulation. In contrast, solar dimming does not produce heating of the tropical lower stratosphere, and so there is little intensification of the polar vortex and no enhanced tropical upwelling. The dynamical response to titania aerosol is qualitatively similar to the response to sulfate.
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This article considers the ways in which British youth telefantasy Misfits (E4, 2009–13) takes up and makes strange urban spaces familiar from social-realist narratives. Filmed on the sprawling East London estate, Thamesmead, the programme chronicles a group of young offenders who are given powers by a freak storm, turning them into ‘ASBO superheroes’. Misfits depends on its British urban landscapes for the assertion of its ‘authenticity’ within British youth television, using spaces and landscapes familiar from urban youth exploitation cinema and television's narratives of the underclass. After situating the series within existing cultural discourses and recent developments in social-realist representations, the article explores how Misfits disrupts what have become signifiers for the ‘real’ – the brutalism of housing estates, the grey of the concrete and sky – by making them strange, turning them into telefantasy. The series presents the estate as an uncanny place: the domestic, social-realist world shifted into a fantastical space by the storm. Through close analysis, this article explores how the familiar spaces become skewed and unsettling to match our protagonists' isolation, shifting bodies and scrambled sense of self.
Resumo:
The dance film flourished in the 2000s in the form of the hip-hop teen dance film. Such films as Save the Last Dance (Thomas Carter, 2001), Honey (Billy Woodruff, 2002) and Step Up (Anne Fletcher, 2006) drew on hip-hop’s dominance of the mainstream music industry and combined the teen film’s pre-existing social problem and musical narratives. Yet various tension were created by their interweaving of representations of post-industrial city youth with the utopian sensibilities of the classical Hollywood musical. Their narratives celebrated hip-hop performance, and depicted dance’s ability to bridge cultural boundaries and bring together couples and communities. These films used hip-hop to define space and identity yet often constructed divisions within their soundscapes, limiting hip-hop’s expressive potential. This article explores the cycle’s celebration of, yet struggle with, hip-hop through examining select films’ interactions between soundscape, narrative and form. It will engage with these films’ attempts to marry the representational, narrative and aesthetic meanings of hip-hop culture with the form and ideologies of the musical genre, particularly the tensions and continuities that arise from their engagement with the genre’s utopian qualities identified by Richard Dyer (1985). Yet whilst these films illustrate the tensions and challenges of combining hip-hop culture and the musical genre, they also demonstrate an effective integration of hip-hop soundscape and the dancing body in their depiction of dance, highlighting both form’s aesthetics of layering, rupture and flow (Rose, 1994: 22).
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Collocations between two satellite sensors are occasions where both sensors observe the same place at roughly the same time. We study collocations between the Microwave Humidity Sounder (MHS) on-board NOAA-18 and the Cloud Profiling Radar (CPR) on-board CloudSat. First, a simple method is presented to obtain those collocations and this method is compared with a more complicated approach found in literature. We present the statistical properties of the collocations, with particular attention to the effects of the differences in footprint size. For 2007, we find approximately two and a half million MHS measurements with CPR pixels close to their centrepoints. Most of those collocations contain at least ten CloudSat pixels and image relatively homogeneous scenes. In the second part, we present three possible applications for the collocations. Firstly, we use the collocations to validate an operational Ice Water Path (IWP) product from MHS measurements, produced by the National Environment Satellite, Data and Information System (NESDIS) in the Microwave Surface and Precipitation Products System (MSPPS). IWP values from the CloudSat CPR are found to be significantly larger than those from the MSPPS. Secondly, we compare the relation between IWP and MHS channel 5 (190.311 GHz) brightness temperature for two datasets: the collocated dataset, and an artificial dataset. We find a larger variability in the collocated dataset. Finally, we use the collocations to train an Artificial Neural Network and describe how we can use it to develop a new MHS-based IWP product. We also study the effect of adding measurements from the High Resolution Infrared Radiation Sounder (HIRS), channels 8 (11.11 μm) and 11 (8.33 μm). This shows a small improvement in the retrieval quality. The collocations described in the article are available for public use.
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A strong body of work has explored the interaction between visual perception and language comprehension; for example, recent studies exploring predictions from embodied cognition have focused particularly on the common representation of sensory—motor and semantic information. Motivated by this background, we provide a set of norms for the axis and direction of motion implied in 299 English verbs, collected from approximately 100 native speakers of British English. Until now, there have been no freely available norms of this kind for a large set of verbs that can be used in any area of language research investigating the semantic representation of motion. We have used these norms to investigate the interaction between language comprehension and low-level visual processes involved in motion perception, validating the norming procedure’s ability to capture the motion content of individual verbs. Supplemental materials for this study may be downloaded from brm.psychonomic-journals.org/content/supplemental.