14 resultados para Local Scale

em Aston University Research Archive


Relevância:

60.00% 60.00%

Publicador:

Resumo:

Marr's work offered guidelines on how to investigate vision (the theory - algorithm - implementation distinction), as well as specific proposals on how vision is done. Many of the latter have inevitably been superseded, but the approach was inspirational and remains so. Marr saw the computational study of vision as tightly linked to psychophysics and neurophysiology, but the last twenty years have seen some weakening of that integration. Because feature detection is a key stage in early human vision, we have returned to basic questions about representation of edges at coarse and fine scales. We describe an explicit model in the spirit of the primal sketch, but tightly constrained by psychophysical data. Results from two tasks (location-marking and blur-matching) point strongly to the central role played by second-derivative operators, as proposed by Marr and Hildreth. Edge location and blur are evaluated by finding the location and scale of the Gaussian-derivative `template' that best matches the second-derivative profile (`signature') of the edge. The system is scale-invariant, and accurately predicts blur-matching data for a wide variety of 1-D and 2-D images. By finding the best-fitting scale, it implements a form of local scale selection and circumvents the knotty problem of integrating filter outputs across scales. [Supported by BBSRC and the Wellcome Trust]

Relevância:

60.00% 60.00%

Publicador:

Resumo:

In this article, we discuss the advisory capacity of climate science for political and societal decisions. To provide options, open up perspectives and enhance the understanding for the dynamics of climate is a task we name climate services. After a general discussion, experiences of providing these services on a regional and local scale – Northern Germany, the metropolitan area of Hamburg and the Baltic Sea Basin – during the last few years is reviewed.Key components of this regional climate service is the establishment of a regional climate office, of regional IPCC-like assessments of knowledge about regional and local climate change, and detailed homogeneous data sets describing changing weather statistics (i.e., climate) in past decades and in perspectives for the next several decades.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Many local authorities (LAs) are currently working to reduce both greenhouse gas emissions and the amount of municipal solid waste (MSW) sent to landfill. The recovery of energy from waste (EfW) can assist in meeting both of these objectives. The choice of an EfW policy combines spatial and non-spatial decisions which may be handled using Multi-Criteria Analysis (MCA) and Geographic Information Systems (GIS). This paper addresses the impact of transporting MSW to EfW facilities, analysed as part of a larger decision support system designed to make an overall policy assessment of centralised (large-scale) and distributed (local-scale) approaches. Custom-written ArcMap extensions are used to compare centralised versus distributed approaches, using shortest-path routing based on expected road speed. Results are intersected with 1-kilometre grids and census geographies for meaningful maps of cumulative impact. Case studies are described for two counties in the United Kingdom (UK); Cornwall and Warwickshire. For both case study areas, centralised scenarios generate more traffic, fuel costs and emitted carbon per tonne of MSW processed.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Different procurement decisions taken by relief organizations can result in considerably different implications in regards to transport, storage, and distribution of humanitarian aid and ultimately can influence the performance of the humanitarian supply chain and the delivery of the humanitarian aid. In this article, we look into what resources are needed and how these resources evolve in the delivery of humanitarian aid. Drawing on the resource-based view of the firm, we develop a framework to categorize the impact of local resources on the configuration of humanitarian supply chains. In contrast to other papers, the importance of localizing the configuration of the humanitarian supply chain is not only conceptually recognized, but empirical investigations are also provided. In terms of methodology, this article is based on the analysis of secondary data from two housing reconstruction projects. Findings indicate that the use of local resources in humanitarian aid has positive effects on programs' overall supply chain performance and these effects are not only related to the macroeconomic perspective, but benefits expand to improvements related to the use of knowledge. At the same time, it was found that local sourcing often comes with a number of problems. For example, in one of the cases, significant problems existed, which were related to the scarcity of local supplies. Both housing reconstruction projects have indicated the continuous need for changes throughout the programs as a dynamic supply chain configuration is important for the long-term sustainability of reconstruction aid. © 2014 Decision Sciences Institute.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Over the last two decades fundamental changes have taken place in the global supply and local structure of provision of British food retailing. Consumer lifestyles have also changed markedly. Despite some important studies of local interactions between new retail developments and consumers, we argue in this paper that there is a critical need to gauge the cumulative effects of these changes on consumer behaviour over longer periods. In this, the first of two papers, we present the main findings of a study of the effects of long-term retail change on consumers at the local level. We provide in this paper an overview of the changing geography of retail provision and patterns of consumption at the local level. We contextualise the Portsmouth study area as a locality that typifies national changes in retail provision and consumer lifestyles; outline the main findings of two large-scale surveys of food shopping behaviour carried out in 1980 and 2002; and reveal the impacts of retail restructuring on consumer behaviour. We focus in particular on choice between stores at the local level and end by problematising our understanding of how consumers experience choice, emphasising the need for qualitative research. This issue is then dealt with in our complementary second paper, which explores choice within stores and how this relates to the broader spatial context.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The Foot-and-Mouth Disease (FMD) outbreak of 2001 in the UK was completely unprecedented in its scale and severity, with over four million animals culled and a cost to the Exchequer of over £4 billion. Local authorities were at the front line in dealing with the outbreak, in coordinating the cull of livestock, the disposal of carcasses as well as attempting to deal with its aftermath and, in particular, the impact on the wider rural economy. This article examines the impacts of this crisis on three local authorities, Devon, Herefordshire and Cumbria. It examines how far the crisis acted as a catalyst in developing strategies to deal with a future outbreak as well as new local initiatives to promote regeneration in the areas most adversely affected. It focuses on developments that can be directly attributed to the crisis and shows that FMD had a considerable impact on communications and 'joined-up' activity within local authorities and with local stakeholders. © 2006, LEPU, South Bank University.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Edges are key points of information in visual scenes. One important class of models supposes that edges correspond to the steepest parts of the luminance profile, implying that they can be found as peaks and troughs in the response of a gradient (1st derivative) filter, or as zero-crossings in the 2nd derivative (ZCs). We tested those ideas using a stimulus that has no local peaks of gradient and no ZCs, at any scale. The stimulus profile is analogous to the Mach ramp, but it is the luminance gradient (not the absolute luminance) that increases as a linear ramp between two plateaux; the luminance profile is a blurred triangle-wave. For all image-blurs tested, observers marked edges at or close to the corner points in the gradient profile, even though these were not gradient maxima. These Mach edges correspond to peaks and troughs in the 3rd derivative. Thus Mach edges are inconsistent with many standard edge-detection schemes, but are nicely predicted by a recent model that finds edge points with a 2-stage sequence of 1st then 2nd derivative operators, each followed by a half-wave rectifier.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Perception of Mach bands may be explained by spatial filtering ('lateral inhibition') that can be approximated by 2nd derivative computation, and several alternative models have been proposed. To distinguish between them, we used a novel set of ‘generalised Gaussian’ images, in which the sharp ramp-plateau junction of the Mach ramp was replaced by smoother transitions. The images ranged from a slightly blurred Mach ramp to a Gaussian edge and beyond, and also included a sine-wave edge. The probability of seeing Mach Bands increased with the (relative) sharpness of the junction, but was largely independent of absolute spatial scale. These data did not fit the predictions of MIRAGE, nor 2nd derivative computation at a single fine scale. In experiment 2, observers used a cursor to mark features on the same set of images. Data on perceived position of Mach bands did not support the local energy model. Perceived width of Mach bands was poorly explained by a single-scale edge detection model, despite its previous success with Mach edges (Wallis & Georgeson, 2009, Vision Research, 49, 1886-1893). A more successful model used separate (odd and even) scale-space filtering for edges and bars, local peak detection to find candidate features, and the MAX operator to compare odd- and even-filter response maps (Georgeson, VSS 2006, Journal of Vision 6(6), 191a). Mach bands are seen when there is a local peak in the even-filter (bar) response map, AND that peak value exceeds corresponding responses in the odd-filter (edge) maps.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Forests play a pivotal role in timber production, maintenance and development of biodiversity and in carbon sequestration and storage in the context of the Kyoto Protocol. Policy makers and forest experts therefore require reliable information on forest extent, type and change for management, planning and modeling purposes. It is becoming increasingly clear that such forest information is frequently inconsistent and unharmonised between countries and continents. This research paper presents a forest information portal that has been developed in line with the GEOSS and INSPIRE frameworks. The web portal provides access to forest resources data at a variety of spatial scales, from global through to regional and local, as well as providing analytical capabilities for monitoring and validating forest change. The system also allows for the utilisation of forest data and processing services within other thematic areas. The web portal has been developed using open standards to facilitate accessibility, interoperability and data transfer.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In a Data Envelopment Analysis model, some of the weights used to compute the efficiency of a unit can have zero or negligible value despite of the importance of the corresponding input or output. This paper offers an approach to preventing inputs and outputs from being ignored in the DEA assessment under the multiple input and output VRS environment, building on an approach introduced in Allen and Thanassoulis (2004) for single input multiple output CRS cases. The proposed method is based on the idea of introducing unobserved DMUs created by adjusting input and output levels of certain observed relatively efficient DMUs, in a manner which reflects a combination of technical information and the decision maker's value judgements. In contrast to many alternative techniques used to constrain weights and/or improve envelopment in DEA, this approach allows one to impose local information on production trade-offs, which are in line with the general VRS technology. The suggested procedure is illustrated using real data. © 2011 Elsevier B.V. All rights reserved.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Current British government economic development policy emphasises regional and sub-regional scale, multi-agent initiatives that form part of national frameworks to encourage a 'bottom up' approach to economic development. An emphasis on local multi-agent initiatives was also the mission of Training and Enterprise Councils (TECs). Using new survey evidence this article tracks the progress of a number of initiatives established under the TECs, using the TEC Discretionary Fund as an example. It assesses the ability of successor bodies to be more effective in promoting local economic development. Survey evidence is used to confirm that many projects previously set up by the TECs continue to operate successfully under new partnership arrangements. However as new structures have developed, and policy has become more centralized, it is less likely that similar local initiatives will be developed in future. There is evidence to suggest that with the end of the TECs a gap has emerged in the institutional infrastructure for local economic development, particularly with regard to workforce development. Much will depend in future on how the Regional Development Agencies deploy their growing power and resources.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Post-disaster recovery of Micro, Small and Medium-Scale Enterprises (SMEs) remains an issue of interest for policy and practice given the wide scale occurrences of natural disasters around the globe and their significant impacts on local economies and SMEs. Asian Tsunami of December 2004 affected many SMEs in southern Sri Lanka. The study was developed to identify the main issues encountered by the Tsunami affected SMEs in Southern Sri Lanka in the process of their post-tsunami recovery. The study: a) identifies tsunami damage and loss in micro and SMEs in the Galle district; b) ascertains the type of benefits received from various parties by the affected micro and SMEs; c) evaluates the problems and difficulties faced by the beneficiary organizations in the benefit distribution process; and d) recommends strategies and policies for the tsunami-affected micro and SMEs for them to become self-sustaining within a reasonable time frame. Fifty randomly selected tsunami-affected micro and SMEs were surveyed for this study. Interviews were conducted in person with the business owners in order to identify the damages, recovery, rehabilitation, re-establishment and difficulties faced in the benefit distribution process. The analysis identifies that the benefits were given the wrong priorities and that they were not sufficient for the recovery process. In addition, the many governance-related problems that arose while distributing benefits are discussed. Overall, the business recovery rate was approximately 65%, and approximately 88% of business organizations were sole proprietorships. Therefore, the policies of the tsunami relief agencies should adequately address the needs of sole proprietorship business requirements. Consideration should also be given to strengthen the capacity and skills of the entrepreneurs by improving operational, technological, management and marketing skills and capabilities.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Purpose – The purpose of this paper is to explore the importance of host country networks and organisation of production in the context of international technology transfer that accompanies foreign direct investment (FDI). Design/methodology/approach – The empirical analysis is based on unbalanced panel data covering Japanese firms active in two-digit manufacturing sectors over a seven-year period. Given the self-selection problem affecting past sectoral-level studies, using firm-level panel data is a prerequisite to provide robust empirical evidence. Findings – While Japan is thought of as being a technologically advanced country, the results show that vertical productivity spillovers from FDI occur in Japan, but they are sensitive to technological differences between domestic firms and the idiosyncratic Japanese institutional network. FDI in vertically organised keiretsu sectors generates inter-industry spillovers through backward and forward linkages, while FDI within sectors linked to vertical keiretsu activities adversely affects domestic productivity. Overall, our results suggest that the role of vertical keiretsu is more prevalent than that of horizontal keiretsu. Originality/value – Japan’s industrial landscape has been dominated by institutional clusters or networks of inter-firm organisations through reciprocated, direct and indirect ties. However, interactions between inward investors and such institutionalised networks in the host economy are seldom explored. The role and characteristics of local business groups, in the form of keiretsu networks, have been investigated to determine the scale and scope of spillovers from inward FDI to Japanese establishments. This conceptualisation depends on the institutional mechanism and the market structure through which host economies absorb and exploit FDI.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In studies of complex heterogeneous networks, particularly of the Internet, significant attention was paid to analysing network failures caused by hardware faults or overload. There network reaction was modelled as rerouting of traffic away from failed or congested elements. Here we model network reaction to congestion on much shorter time scales when the input traffic rate through congested routes is reduced. As an example we consider the Internet where local mismatch between demand and capacity results in traffic losses. We describe the onset of congestion as a phase transition characterised by strong, albeit relatively short-lived, fluctuations of losses caused by noise in input traffic and exacerbated by the heterogeneous nature of the network manifested in a power-law load distribution. The fluctuations may result in the network strongly overreacting to the first signs of congestion by significantly reducing input traffic along the communication paths where congestion is utterly negligible. © 2013 IEEE.