84 resultados para conceptual map

em CentAUR: Central Archive University of Reading - UK


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We describe ncWMS, an implementation of the Open Geospatial Consortium’s Web Map Service (WMS) specification for multidimensional gridded environmental data. ncWMS can read data in a large number of common scientific data formats – notably the NetCDF format with the Climate and Forecast conventions – then efficiently generate map imagery in thousands of different coordinate reference systems. It is designed to require minimal configuration from the system administrator and, when used in conjunction with a suitable client tool, provides end users with an interactive means for visualizing data without the need to download large files or interpret complex metadata. It is also used as a “bridging” tool providing interoperability between the environmental science community and users of geographic information systems. ncWMS implements a number of extensions to the WMS standard in order to fulfil some common scientific requirements, including the ability to generate plots representing timeseries and vertical sections. We discuss these extensions and their impact upon present and future interoperability. We discuss the conceptual mapping between the WMS data model and the data models used by gridded data formats, highlighting areas in which the mapping is incomplete or ambiguous. We discuss the architecture of the system and particular technical innovations of note, including the algorithms used for fast data reading and image generation. ncWMS has been widely adopted within the environmental data community and we discuss some of the ways in which the software is integrated within data infrastructures and portals.

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Flood modelling of urban areas is still at an early stage, partly because until recently topographic data of sufficiently high resolution and accuracy have been lacking in urban areas. However, Digital Surface Models (DSMs) generated from airborne scanning laser altimetry (LiDAR) having sub-metre spatial resolution have now become available, and these are able to represent the complexities of urban topography. The paper describes the development of a LiDAR post-processor for urban flood modelling based on the fusion of LiDAR and digital map data. The map data are used in conjunction with LiDAR data to identify different object types in urban areas, though pattern recognition techniques are also employed. Post-processing produces a Digital Terrain Model (DTM) for use as model bathymetry, and also a friction parameter map for use in estimating spatially-distributed friction coefficients. In vegetated areas, friction is estimated from LiDAR-derived vegetation height, and (unlike most vegetation removal software) the method copes with short vegetation less than ~1m high, which may occupy a substantial fraction of even an urban floodplain. The DTM and friction parameter map may also be used to help to generate an unstructured mesh of a vegetated urban floodplain for use by a 2D finite element model. The mesh is decomposed to reflect floodplain features having different frictional properties to their surroundings, including urban features such as buildings and roads as well as taller vegetation features such as trees and hedges. This allows a more accurate estimation of local friction. The method produces a substantial node density due to the small dimensions of many urban features.

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This paper proposes a conceptual model of a context-aware group support system (GSS) to assist local council employees to perform collaborative tasks in conjunction with inter- and intra-organisational stakeholders. Most discussions about e-government focus on the use of ICT to improve the relationship between government and citizen, not on the relationship between government and employees. This paper seeks to expose the unique culture of UK local councils and to show how a GSS could support local government employer and employee needs.

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This paper argues for the importance of retaining a map library presence on UK university campuses at a time when many are under threat of closure, and access to geospatial data is increasingly moving to web-based services. It is suggested that the need for local expertise is undiminished and map curators need to redefine themselves as geoinformation specialists, preserving their paper map collections, but also meeting some of the challenges of GIS, and contributing to national developments in the construction of distributed geolibraries and the provision of metadata, especially with regard to local data sets.

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Across Europe, elevated phosphorus (P) concentrations in lowland rivers have made them particularly susceptible to eutrophication. This is compounded in southern and central UK by increasing pressures on water resources, which may be further enhanced by the potential effects of climate change. The EU Water Framework Directive requires an integrated approach to water resources management at the catchment scale and highlights the need for modelling tools that can distinguish relative contributions from multiple nutrient sources and are consistent with the information content of the available data. Two such models are introduced and evaluated within a stochastic framework using daily flow and total phosphorus concentrations recorded in a clay catchment typical of many areas of the lowland UK. Both models disaggregate empirical annual load estimates, derived from land use data, as a function of surface/near surface runoff, generated using a simple conceptual rainfall-runoff model. Estimates of the daily load from agricultural land, together with those from baseflow and point sources, feed into an in-stream routing algorithm. The first model assumes constant concentrations in runoff via surface/near surface pathways and incorporates an additional P store in the river-bed sediments, depleted above a critical discharge, to explicitly simulate resuspension. The second model, which is simpler, simulates P concentrations as a function of surface/near surface runoff, thus emphasising the influence of non-point source loads during flow peaks and mixing of baseflow and point sources during low flows. The temporal consistency of parameter estimates and thus the suitability of each approach is assessed dynamically following a new approach based on Monte-Carlo analysis. (c) 2004 Elsevier B.V. All rights reserved.

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The beds of active ice streams in Greenland and Antarctica are largely inaccessible, hindering a full understanding of the processes that initiate, sustain and inhibit fast ice flow in ice sheets. Detailed mapping of the glacial geomorphology of palaeo-ice stream tracks is, therefore, a valuable tool for exploring the basal processes that control their behaviour. In this paper we present a map that shows detailed glacial geomorphology from a part of the Dubawnt Lake Palaeo-Ice Stream bed on the north-western Canadian Shield (Northwest Territories), which operated at the end of the last glacial cycle. The map (centred on 63 degrees 55 '' 42'N, 102 degrees 29 '' 11'W, approximate scale 1:90,000) was compiled from digital Landsat Enhanced Thematic Mapper Plus satellite imagery and digital and hard-copy stereo-aerial photographs. The ice stream bed is dominated by parallel mega-scale glacial lineations (MGSL), whose lengths exceed several kilometres but the map also reveals that they have, in places, been superimposed with transverse ridges known as ribbed moraines. The ribbed moraines lie on top of the MSGL and appear to have segmented the individual lineaments. This indicates that formation of the ribbed moraines post-date the formation of the MSGL. The presence of ribbed moraine in the onset zone of another palaeo-ice stream has been linked to oscillations between cold and warm-based ice and/or a patchwork of cold-based areas which led to acceleration and deceleration of ice velocity. Our hypothesis is that the ribbed moraines on the Dubawnt Lake Ice Stream bed are a manifestation of the process that led to ice stream shut-down and may be associated with the process of basal freeze-on. The precise formation of ribbed moraines, however, remains open to debate and field observation of their structure will provide valuable data for formal testing of models of their formation.

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Victoria Island lies at the north-western extremity of the region covered by the vast North American Laurentide Ice Sheet (LIS) in the Canadian Arctic Archipelago. This area is significant because it linked the interior of the LIS to the Arctic Ocean, probably via a number of ice streams. Victoria Island, however, exhibits a remarkably complex glacial landscape, with several successive generations of ice flow indicators superimposed on top of each other and often at abrupt (90 degrees) angles. This complexity represents a major challenge to those attempting to produce a detailed reconstruction of the glacial history of the region. This paper presents a map of the glacial geomorphology of Victoria Island. The map is based on analysis of Landsat Enhanced Thematic Plus (ETM+) satellite imagery and contains over 58,000 individual glacial features which include: glacial lineations, moraines (terminal, lateral, subglacial shear margin), hummocky moraine, ribbed moraine, eskers, glaciofluvial deposits, large meltwater channels, and raised shorelines. The glacial features reveal marked changes in ice flow direction and vigour over time. Moreover, the glacial geomorphology indicates a non-steady withdrawal of ice during deglaciation, with rapidly flowing ice streams focussed into the inter-island troughs and several successively younger flow patterns superimposed on older ones. It is hoped that detailed analysis of this map will lead to an improved reconstruction of the glacial history of this area which will provide other important insights, for example, with respect to the interactions between ice streaming, deglaciation and Arctic Ocean meltwater events.

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In order to gain a better understanding of online conceptual collaborative design processes this paper investigates how student designers make use of a shared virtual synchronous environment when engaged in conceptual design. The software enables users to talk to each other and share sketches when they are remotely located. The paper describes a novel methodology for observing and analysing collaborative design processes by adapting the concepts of grounded theory. Rather than concentrating on narrow aspects of the final artefacts, emerging “themes” are generated that provide a broader picture of collaborative design process and context descriptions. Findings on the themes of “grounding – mutual understanding” and “support creativity” complement findings from other research, while important themes associated with “near-synchrony” have not been emphasised in other research. From the study, a series of design recommendations are made for the development of tools to support online computer-supported collaborative work in design using a shared virtual environment.

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The community pharmacy service medicines use review (MUR) was introduced in 2005 ‘to improve patient knowledge, concordance and use of medicines’ through a private patient–pharmacist consultation. The MUR presents a fundamental change in community pharmacy service provision. While traditionally pharmacists are dispensers of medicines and providers of medicines advice, and patients as recipients, the MUR considers pharmacists providing consultation-type activities and patients as active participants. The MUR facilitates a two-way discussion about medicines use. Traditional patient–pharmacist behaviours transform into a new set of behaviours involving the booking of appointments, consultation processes and form completion, and the physical environment of the patient–pharmacist interaction moves from the traditional setting of the dispensary and medicines counter to a private consultation room. Thus, the new service challenges traditional identities and behaviours of the patient and the pharmacist as well as the environment in which the interaction takes place. In 2008, the UK government concluded there is at present too much emphasis on the quantity of MURs rather than on their quality.[1] A number of plans to remedy the perceived imbalance included a suggestion to reward ‘health outcomes’ achieved, with calls for a more focussed and scientific approach to the evaluation of pharmacy services using outcomes research. Specifically, the UK government set out the main principal research areas for the evaluation of pharmacy services to include ‘patient and public perceptions and satisfaction’as well as ‘impact on care and outcomes’. A limited number of ‘patient satisfaction with pharmacy services’ type questionnaires are available, of varying quality, measuring dimensions relating to pharmacists’ technical competence, behavioural impressions and general satisfaction. For example, an often cited paper by Larson[2] uses two factors to measure satisfaction, namely ‘friendly explanation’ and ‘managing therapy’; the factors are highly interrelated and the questions somewhat awkwardly phrased, but more importantly, we believe the questionnaire excludes some specific domains unique to the MUR. By conducting patient interviews with recent MUR recipients, we have been working to identify relevant concepts and develop a conceptual framework to inform item development for a Patient Reported Outcome Measure questionnaire bespoke to the MUR. We note with interest the recent launch of a multidisciplinary audit template by the Royal Pharmaceutical Society of Great Britain (RPSGB) in an attempt to review the effectiveness of MURs and improve their quality.[3] This template includes an MUR ‘patient survey’. We will discuss this ‘patient survey’ in light of our work and existing patient satisfaction with pharmacy questionnaires, outlining a new conceptual framework as a basis for measuring patient satisfaction with the MUR. Ethical approval for the study was obtained from the NHS Surrey Research Ethics Committee on 2 June 2008. References 1. Department of Health (2008). Pharmacy in England: Building on Strengths – Delivering the Future. London: HMSO. www. official-documents.gov.uk/document/cm73/7341/7341.pdf (accessed 29 September 2009). 2. Larson LN et al. Patient satisfaction with pharmaceutical care: update of a validated instrument. JAmPharmAssoc 2002; 42: 44–50. 3. Royal Pharmaceutical Society of Great Britain (2009). Pharmacy Medicines Use Review – Patient Audit. London: RPSGB. http:// qi4pd.org.uk/index.php/Medicines-Use-Review-Patient-Audit. html (accessed 29 September 2009).

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In this work a new method for clustering and building a topographic representation of a bacteria taxonomy is presented. The method is based on the analysis of stable parts of the genome, the so-called “housekeeping genes”. The proposed method generates topographic maps of the bacteria taxonomy, where relations among different type strains can be visually inspected and verified. Two well known DNA alignement algorithms are applied to the genomic sequences. Topographic maps are optimized to represent the similarity among the sequences according to their evolutionary distances. The experimental analysis is carried out on 147 type strains of the Gammaprotebacteria class by means of the 16S rRNA housekeeping gene. Complete sequences of the gene have been retrieved from the NCBI public database. In the experimental tests the maps show clusters of homologous type strains and present some singular cases potentially due to incorrect classification or erroneous annotations in the database.

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Many producers of geographic information are now disseminating their data using open web service protocols, notably those published by the Open Geospatial Consortium. There are many challenges inherent in running robust and reliable services at reasonable cost. Cloud computing provides a new kind of scalable infrastructure that could address many of these challenges. In this study we implement a Web Map Service for raster imagery within the Google App Engine environment. We discuss the challenges of developing GIS applications within this framework and the performance characteristics of the implementation. Results show that the application scales well to multiple simultaneous users and performance will be adequate for many applications, although concerns remain over issues such as latency spikes. We discuss the feasibility of implementing services within the free usage quotas of Google App Engine and the possibility of extending the approaches in this paper to other GIS applications.