466 research outputs found

    A user-centred evaluation framework for the Sealife semantic web browsers

    Get PDF
    Background: Semantically-enriched browsing has enhanced the browsing experience by providing contextualised dynamically generated Web content, and quicker access to searched-for information. However, adoption of Semantic Web technologies is limited and user perception from the non-IT domain sceptical. Furthermore, little attention has been given to evaluating semantic browsers with real users to demonstrate the enhancements and obtain valuable feedback. The Sealife project investigates semantic browsing and its application to the life science domain. Sealife's main objective is to develop the notion of context-based information integration by extending three existing Semantic Web browsers (SWBs) to link the existing Web to the eScience infrastructure. / Methods: This paper describes a user-centred evaluation framework that was developed to evaluate the Sealife SWBs that elicited feedback on users' perceptions on ease of use and information findability. Three sources of data: i) web server logs; ii) user questionnaires; and iii) semi-structured interviews were analysed and comparisons made between each browser and a control system. / Results: It was found that the evaluation framework used successfully elicited users' perceptions of the three distinct SWBs. The results indicate that the browser with the most mature and polished interface was rated higher for usability, and semantic links were used by the users of all three browsers. / Conclusion: Confirmation or contradiction of our original hypotheses with relation to SWBs is detailed along with observations of implementation issues

    Social Capital and Housing Tenure in an Adelaide Neighbourhood

    Get PDF
    Author version made available in accordance with publisher copyright policy.In this paper we compare and contrast elements of social capital across different housing tenures in an Adelaide neighbourhood. Using the results of 530 self-completion questionnaires and in-depth qualitative interviews with 16 people we assess perceptions of conflict across housing tenures and between socioeconomic groups, feelings of acceptance and belonging in the local neighbourhood, and levels of involvement in local formal and informal networks. While only a small number of questionnaire respondents reported negative views of socioeconomic diversity in the area a common theme emerging in the qualitative data indicated that housing tenure was relevant to some of these negative perceptions. Respondents from across different tenure types also reported differences in feelings of acceptance in the neighbourhood, and involvement in formal and informal networks. The study findings suggest that housing tenure is relevant to the development of neighbourhood-based social capital, and that this factor needs to be considered by social planners, housing policy makers and others involved in implementing social mix policies. In addition, the findings indicate the need to consider the community housing and public housing tenures in their own right, given the different models of housing provision, rather than collectively under the common banner of social housing as most research studies do. It is recommended that the full diversity of housing tenure is considered in any future analysis

    Predictive use of the Maximum Entropy Production principle for Past and Present Climates

    Full text link
    In this paper, we show how the MEP hypothesis may be used to build simple climate models without representing explicitly the energy transport by the atmosphere. The purpose is twofold. First, we assess the performance of the MEP hypothesis by comparing a simple model with minimal input data to a complex, state-of-the-art General Circulation Model. Next, we show how to improve the realism of MEP climate models by including climate feedbacks, focusing on the case of the water-vapour feedback. We also discuss the dependence of the entropy production rate and predicted surface temperature on the resolution of the model

    Rank-based model selection for multiple ions quantum tomography

    Get PDF
    The statistical analysis of measurement data has become a key component of many quantum engineering experiments. As standard full state tomography becomes unfeasible for large dimensional quantum systems, one needs to exploit prior information and the "sparsity" properties of the experimental state in order to reduce the dimensionality of the estimation problem. In this paper we propose model selection as a general principle for finding the simplest, or most parsimonious explanation of the data, by fitting different models and choosing the estimator with the best trade-off between likelihood fit and model complexity. We apply two well established model selection methods -- the Akaike information criterion (AIC) and the Bayesian information criterion (BIC) -- to models consising of states of fixed rank and datasets such as are currently produced in multiple ions experiments. We test the performance of AIC and BIC on randomly chosen low rank states of 4 ions, and study the dependence of the selected rank with the number of measurement repetitions for one ion states. We then apply the methods to real data from a 4 ions experiment aimed at creating a Smolin state of rank 4. The two methods indicate that the optimal model for describing the data lies between ranks 6 and 9, and the Pearson χ2\chi^{2} test is applied to validate this conclusion. Additionally we find that the mean square error of the maximum likelihood estimator for pure states is close to that of the optimal over all possible measurements.Comment: 24 pages, 6 figures, 3 table

    Interpretation of the Global Anisotropy in the Radio Polarizations of Cosmologically Distant Sources

    Full text link
    We present a detailed statistical study of the observed anisotropy in radio polarizations from distant extragalactic objects. This anisotropy was earlier found by Birch (1982) and reconfirmed by Jain and Ralston (1999) in a larger data set. A very strong signal was seen after imposing the cut RMRMˉ>6|RM-\bar{RM}|>6 rad/m2^2, where RMRM is the rotation measure and RMˉ\bar{RM} its mean value. In this paper we show that there are several indications that this anisotropy cannot be attributed to bias in the data. We also find that a generalized statistic shows a very strong signal in the entire data without imposing the RM dependent cut. Finally we argue that an anisotropic background pseudoscalar field can explain the observations.Comment: 13 pages, 6 figure

    Spaces of death in Emily Brontë’s Wuthering Heights

    Get PDF
    In this article I explore the idea expressed by philosophers and social geographers such as Henri Lefebvre, Edward Soja, and Henk van Houtum that “space” is a social construct; that the space in which a society exists and of which it consists is shaped by that society itself, and that specific locations are assigned to each of the members of the community. I discuss how the dominant spaces in society are shaped by those in positions of authority according to their own ideologies so as to ensure social order and their continued empowerment within the social structure. Additionally, I suggest that it is possible for those who do not conform to social norms, and who are consequently cast into dominated spaces, to undermine the authority of those in positions of power by embracing their marginalised state, and thereby to generate new spaces they can inhabit. I explore these ideas in relation to Emily Brontë’s Wuthering Heights and its depiction and examination of central nineteenth-century ideas and anxieties about death and the different areas allocated to the dead.In hierdie artikel ondersoek ek die idee, verwoord deur filosowe en sosiale geograwe soos Henri Lefebvre, Edward Soja en Henk van Houtum, dat “ruimte” ’n sosiale skepping is; dat die ruimte waarin ’n gemeenskap geleë is en waaruit dit bestaan deur die samelewing self gevorm word en dat spesifieke ruimtes aan elk van die lede van die gemeenskap toegeken word. Ek bespreek hoe die dominante spasies in die samelewing deur dié in posisies van outoriteit in ooreenstemming met hul eie ideologieë geskep word om sosiale orde en die voortbestaan van hul eie mag binne die sosiale struktuur te verseker. Ek voer ook aan dat dit moontlik is vir dié wat nie by sosiale norme hou nie en wat gevolglik in ruimtes van onderdrukking gewerp word om die outoriteit van dié in magsposisies te ondermyn en sodoende nuwe ruimtes vir hulself te skep. Ek ondersoek hierdie idees ten opsigte van Emily Brontë se Wuthering Heights en dié teks se uitbeelding en ondersoeking van kern negentiende-eeuse idees en vrese met betrekking tot die dood en die verskeie areas wat aan die dooies toegeken word.http://www.tandfonline.com/loi/rjls20hb201

    The rolling problem: overview and challenges

    Full text link
    In the present paper we give a historical account -ranging from classical to modern results- of the problem of rolling two Riemannian manifolds one on the other, with the restrictions that they cannot instantaneously slip or spin one with respect to the other. On the way we show how this problem has profited from the development of intrinsic Riemannian geometry, from geometric control theory and sub-Riemannian geometry. We also mention how other areas -such as robotics and interpolation theory- have employed the rolling model.Comment: 20 page

    Exploring concepts of health with male prisoners in three category-C English prisons

    Get PDF
    Lay understandings of health and illness have a well established track record and a plethora of research now exists which has examined these issues. However, there is a dearth of research which has examined the perspectives of those who are imprisoned. This paper attempts to address this research gap. The paper is timely given that calls have been made to examine lay perspectives in different geographical locations and a need to re-examine health promotion approaches in prison settings. Qualitative data from thirty-six male sentenced prisoners from three prisons in England were collected. The data was analysed in accordance with Attride-Stirling's (2001) thematic network approach. Although the men's perceptions of health were broadly similar to the general population, some interesting findings emerged which were directly related to prison life and its associated structures. These included access to the outdoors and time out of their prison cell, as well as maintaining relationships with family members through visits. The paper proposes that prisoners' lay views should be given higher priority given that prison health has traditionally been associated with medical treatment and the bio-medical paradigm more generally. It also suggests that in order to fulfil the World Health Organization's (WHO) vision of viewing prisons as health promoting settings, lay views should be recognised to shape future health promotion policy and practice
    corecore