109,300 research outputs found
Examining the influence of cell size and bandwidth size on kernel density estimation crime hotspot maps for predicting spatial patterns of crime
Hotspot mapping is a popular technique used for helping target police patrols and other crime reduction initiatives. There are a number of spatial analysis techniques that can be used for identifying hotspots, but the most popular in recent years is kernel density estimation (KDE). KDE is popular because of the visually appealing way it represents the spatial distribution of crime, and because it is considered to be the most accurate of the commonly used hotspot mapping techniques. To produce KDE outputs, the researcher is required to enter values for two main parameters: the cell size and bandwidth size. To date little research has been conducted on the influence these parameters have on KDE hotspot mapping output, and none has been conducted on the influence these parameter settings have on a hotspot map’s central purpose – to identify where crime may occur in the future. We fill this gap with this research by conducting a number of experiments using different cell size and bandwidth values with crime data on residential burglary and violent assaults. We show that cell size has little influence on KDE crime hotspot maps for predicting spatial patterns of crime, but bandwidth size does have an influence. We conclude by discussing how the findings from this research can help inform police practitioners and researchers make better use of KDE for targeting policing and crime prevention initiatives
Towards a micropositioning system for targeted drug delivery in wireless capsule endoscopy
This paper describes a novel micropositioning mechanism for achieving 1ml of targeted drug delivery within wireless capsule endoscopes. The mechanism allows a needle to be positioned within a 22.5° segment of a cylindrical capsule and be extendible by up to 4mm. The mechanism achieves both these functions using only a single micromotor and occupying a volume of just 200mm³ (including micromotor), this represents only 6.6% of the total available space. Through a detailed stress analysis it has been shown that the proposed mechanism can be fabricated using FDA approved materials and requires a power budget of under 3.3% of the available capacity. It is envisaged this mechanism would empower a new breed of capsule microrobots for therapy in addition to diagnostics for pathologies such as ulcerative colitis and small intestinal Crohn’s disease.Accepted versio
Common trends, cointegration and competitive price behaviour
This article describes a characterisation of competitive market behaviour using the concepts of cointegration analysis. It requires all (n) rms to set prices to follow a single stochastic trend (equivalently the vector of n prices should have cointegrating rank n - 1). This implies that, in the long run, prices are driven by the shocks that impact on all companies, ruling out the possibility that the price set by any one rm is weakly exogenous
Recommended from our members
The class of shareholdings and its impacts on corporate performance: a case of state shareholding composition in Chinese publicly listed companies.
Does the class of shareholdings matter for corporate performance? To address the question, our
paper starts by classifying shareholdings on the basis of the principle of ultimate ownership. At
present, the shareholding structure of Chinese quoted companies is state-dominant in that 84% of
public companies ultimately are found controlled by the state, compared with 16% of non-statecontrolled
ones. In contrast to our identified shareholdings, the Chinese official shareholding
record only reports the state and the legal person share classes that are inevitably ambiguous for
the identification of ultimate owners of public corporations, which in turn has misled many
previous studies in assessing the impact of shareholding classes on performance. Based on our
newly established shareholding classes, we make a nested performance comparison between these
different classes, such as the state direct control versus the state indirect control, and find
significant evidence from the Chinese data that the class of shareholdings does matter for
company performance. The least inefficient shareholding class is the holding companies that are
wholly listed and have focused industrial business through the state indirect control of the
downstream public corporations. This finding provides ground for us to think more about how the
corporate control mechanism could be further improved in China’s current corporate governance
reform
Knowledge management and communities of practice in the private sector: lessons for modernising the National Health Service in England and Wales
The National Health Service (NHS) in England and Wales has embarked upon a radical and farreaching programme of change and reform. However, to date the results of organizational quality and service improvement initiatives in the public sector have been mixed, if not to say disappointing, with anticipated gains often failing to materialize or to be sustained in the longer term. This paper draws on the authors' recent extensive research into one of the principal methodologies for bringing about the sought after step change in the quality of health care in England and Wales. It explores how private sector knowledge management (KM) concepts and practices might contribute to the further development of public sector quality improvement initiatives in general and to the reform of the NHS in particular. Our analysis suggests there have been a number of problems and challenges in practice, not least a considerable naïvety around the issue of knowledge transfer and 'knowledge into practice' within health care organizations. We suggest four broad areas for possible development which also have important implications for other public sector organizations
Biography and vulnerability: Loss, dying and death in the Romantic paintings of JMW Turner (1775-1851)
Copyright@ 2005 Edward Arnold (Publishers) Ltd.Narratives of suffering and vulnerability are an important theme in western art, the humanities and the social sciences. It is argued here that J.M.W. Turner's pictures, like those of many artists, are biographical tales. The central tenet of Turner's romantic art is the arousal of sensation and Turner's pictures include wonderfully evocative `visual poems' on the human experiences of loss, decline, `the fallacies of hope', grief and death. This paper first explores the connections between Turner's biography and his art through a discussion of several of Turner's key paintings. It then moves on to a more in-depth discussion of two pictures painted by Turner in 1842, when he was 67 years old: Peace — Burial at Sea, and War — The Exile and the Rock Limpet. These paintings can be seen as insightful biographical narratives on the embodiment of vulnerability. In conclusion, it is suggested that Turner's paintings of loss and death are valuable exemplars of the capacity of art to meld together biography, narrative, vulnerability, suffering and embodiment
Recommended from our members
Long-run equilibrium price targetting
This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ QASS 2011This article describes a characterisation of competitive market behaviour using the concepts of cointegration analysis. It requires all (n) firms to set prices to follow a single stochastic trend (equivalently the vector of n prices should relate to cointegrating rank n- 1). This implies that, in the long run, prices are driven by the shocks that impact on all companies, ruling out the possibility that the price set by any one firm is weakly exogenous for the set of cointegrating vectors
- …