2,082 research outputs found

    Alternative Interpretation of Sharply Rising E0 Strengths in Transitional Regions

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    It is shown that strong 0+2 -> 0+1 E0 transitions provide a clear signature of phase transitional behavior in finite nuclei. Calculations using the IBA show that these transition strengths exhibit a dramatic and robust increase in spherical-deformed shape transition regions, that this rise matches well the existing data, that the predictions of these E0 transitions remain large in deformed nuclei, and that these properties are intrinsic to the way that collectivity and deformation develop through the phase transitional region in the model, arising from the specific d-boson coherence in the wave functions, and that they do not necessarily require the explicit mixing of normal and intruder configurations from different IBA spaces.Comment: 6 pages, 3 figure

    Integrated Structure and Semantics for Reo Connectors and Petri Nets

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    In this paper, we present an integrated structural and behavioral model of Reo connectors and Petri nets, allowing a direct comparison of the two concurrency models. For this purpose, we introduce a notion of connectors which consist of a number of interconnected, user-defined primitives with fixed behavior. While the structure of connectors resembles hypergraphs, their semantics is given in terms of so-called port automata. We define both models in a categorical setting where composition operations can be elegantly defined and integrated. Specifically, we formalize structural gluings of connectors as pushouts, and joins of port automata as pullbacks. We then define a semantical functor from the connector to the port automata category which preserves this composition. We further show how to encode Reo connectors and Petri nets into this model and indicate applications to dynamic reconfigurations modeled using double pushout graph transformation

    Current Results of the EC-sponsored Catchment Modelling (CatchMod) Cluster

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    To support the Water Framework Directive implementation, much research has been commissioned at both national and European levels. CatchMod is a cluster of these projects, which is focusing on the development of computational catchment models and related tools. This paper presents an overview of the results of the CatchMod cluster to dat

    Boson-conserving one-nucleon transfer operator in the interacting boson model

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    The boson-conserving one-nucleon transfer operator in the interacting boson model (IBA) is reanalyzed. Extra terms are added to the usual form used for that operator. These new terms change generalized seniority by one unit, as the ones considered up to now. The results obtained using the new form for the transfer operator are compared with those obtained with the traditional form in a simple case involving the pseudo-spin Bose-Fermi symmetry UB(6)⊗UF(12)U^{B}(6) \otimes U^F(12) in its UBF(5)⊗UF(2)U^{BF}(5) \otimes U^F(2) limit. Sizeable differences are found. These results are of relevance in the study of transfer reactions to check nuclear supersymmetry and in the description of (\beta)-decay within IBA.Comment: 13 pages, 1 table, 0 figures. To be published in Phys. Rev.

    On the creation of near-surface nitrogen-vacancy centre ensembles by implantation of type Ib diamond

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    Dense, near-surface (within 10 nm) ensembles of nitrogen-vacancy (NV) centres in diamond are rapidly moving into prominence as the workhorse of a variety of envisaged applications, ranging from the imaging of fast-fluctuating magnetic signals to the facilitation of nuclear hyperpolarisation. Unlike their bulk counterparts, near-surface ensembles suffer from charge stability issues and reduced NV formation efficiency due to the diamond surface's role as a vacancy sink during annealing and an electron sink afterwards. To this end, work is ongoing to determine the best methods for producing high-quality ensembles in this regime. Here we examine the prospects for creating such ensembles cost-effectively by implanting nitrogen-rich type Ib diamond with electron donors, aiming to exploit the high bulk nitrogen density to combat surface-induced band bending in the process. This approach has previously been successful at creating deeper ensembles, however we find that in the near-surface regime there are fewer benefits over nitrogen implantation into pure diamond substrates. Our results suggest that control over diamond surface termination during annealing is key to successfully creating high-yield near-surface NV ensembles generally, and implantation into type Ib diamond may be worth revisiting once that has been accomplished.Comment: 7 pages, 3 figure

    Record RF performance of standard 90 nm CMOS technology

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    We have optimized 3 key RF devices realized in standard logic 90 nm CMOS technology and report a record performance in terms of n-MOS maximum oscillation frequency f/sub max/ (280 GHz), varactor tuning range and varactor and inductor quality factor

    Sport, physical activity and the establishment of Health and Wellbeing Boards in Nottingham and Nottinghamshire

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    This paper will examine the emergence of Health and Wellbeing Boards in Nottinghamshire and the City of Nottingham and explore the implications for sport and physical activity. At the time of writing the transfer of responsibilities for Public Health and the establishment of Health and Wellbeing Boards in both the City of Nottingham and within Nottinghamshire County Council are considered to be relatively advanced by the Strategic Health Authorities, the respective local authorities and by the boards of the two Primary Care Trusts. "Shadow"� Health and Well being Board have been established in both authorities and they have been meeting regularly for s everal months. Public health and commissioning staff have also been successfully relocated and new strategies and priorities are starting to emerge. Nottingham and Nottinghamshire have traditionally acknowledged the role of sport and physical activity to the wider determinants of public health and given a relatively high priority to the contribution that sport and physical activity can make to the ir preventative health and early intervention agendas. This paper will look at the transition to Health and Wellbeing boards to assess how the role of sport and physical activity may be changing and to identify opportunities for its contribution to policy and practise in the future. It will examine both the theory and practise behind the emerging governance arr angements, the strategic objectives and priorities, and the developing evidential base for future policy and delivery within the two areas
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