39,860 research outputs found

    Political modernisation and the weakening of sustainable development in Britain

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    Article 28 of Agenda 21 placed elected local authorities at the heart of achieving sustainable development. This required a new balance of environmental, social and economic policies co-ordinated by revitalised democratic local government. However, the context within which this would have to be delivered in the UK was the extensive and ongoing restructuring of sub-national government (i.e. both local and regional government) – a restructuring which has continued apace since then, not least with devolution in Scotland and Wales; the extension of unelected regional government in England; and centrally imposed changes to the local government committee system. In addition a further raft of so-called ‘modernisation’ polices have been implemented with broader social concerns such as ‘well-being’ and ‘community strategies’ within which the core environmental concerns of sustainable development are sidelined - viewed as generally desirable, but, ultimately, as ancillary and not essential. This chapter assesses the cumulative impact of these changes in the nature of sub-national government in Britain on the form and effectiveness of policies for sustainable development

    On the beneficial role of noise in resistive switching

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    We study the effect of external noise on resistive switching. Experimental results on a manganite sample are presented showing that there is an optimal noise amplitude that maximizes the contrast between high and low resistive states. By means of numerical simulations, we study the causes underlying the observed behavior. We find that experimental results can be related to general characteristics of the equations governing the system dynamics.Comment: 4 pages, 5 figure

    Properties of the solutions of delocalised coagulation and inception problems with outflow boundaries

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    Well posedness is established for a family of equations modelling particle populations undergoing delocalised coagulation, advection, inflow and outflow in a externally specified velocity field. Very general particle types are allowed while the spatial domain is a bounded region of dd-dimensional space for which every point lies on exactly one streamline associated with the velocity field. The problem is formulated as a semi-linear ODE in the Banach space of bounded measures on particle position and type space. A local Lipschitz property is established in total variation norm for the propagators (generalised semi-groups) associated with the problem and used to construct a Picard iteration that establishes local existence and global uniqueness for any initial condition. The unique weak solution is shown further to be a differentiable or at least bounded variation strong solution under smoothness assumptions on the parameters of the coagulation interaction. In the case of one spatial dimension strong differentiability is established even for coagulation parameters with a particular bounded variation structure in space. This one dimensional extension establishes the convergence of the simulation processes studied in [Patterson, Stoch. Anal. Appl. 31, 2013] to a unique and differentiable limit

    LETS get real: constraints on the development of Local Exchange Trading Schemes

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    Local Exchange Trading Schemes (LETS) are widely promoted as a new tool for local economic development, but until recently the focus has been on their alleged ‘potential’ rather than the realities of their operation. This paper assesses the practical economic role of LETS by examining the amount of trading conducted, and demonstrates that both the volume of trading and the value of the trades are very low. Drawing on an intensive case study of the first UK LETS created explicitly as part of a local authority’s anti-poverty strategy, explanations for the low levels of participation are suggested, and significant structural constraints on the development of LETS are identified

    Teaching Sport Psychology to the XBox Generation: Further evidence for game-based learning

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    Objective: To extend recent research examining the impact of game-based activities on the learning experience of undergraduate psychology students. Design: A counterbalanced repeated measures design was employed to evaluate students’ learning experiences following their involvement in active game-based learning activities. Method: Students on a Level 5 sport psychology module (N=134) were asked to participate in four practical classes demonstrating the impact of psychological factors (e.g. anxiety) on sports performance. Two sessions were designed for each practical: one included the use of active video games (e.g. Kinect Sports); the other included a traditional active game-based activity (e.g. Reaction Time Game). Students were randomly assigned to one of two groups in order to facilitate counterbalancing and to ensure that all students completed two active video game (AVG) and two non-AVG tasks. Following each practical, students provided ratings of perceived usefulness, interest/engagement, and enjoyment using a seven-point Likert scale. These data will be analysed via one way repeated measures analyses of covariance (ANCOVA), with students’ experience of AVGs being the covariate. The impact of sessions on students’ academic motivation and performance were also assessed and analysed via one-way ANOVAs. Results: Data is currently being collected alongside a semester one module. Results will be reported during the presentation. Conclusions: It is anticipated that the findings will provide further evidence to support the use of AVGs in the teaching of undergraduate psychology, and that the increased sophistication of AVG technology may be harnessed to provide multiple benefits for students in higher education

    Bilinear Coagulation Equations

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    We consider coagulation equations of Smoluchowski or Flory type where the total merge rate has a bilinear form π(y)⋅Aπ(x)\pi(y)\cdot A\pi(x) for a vector of conserved quantities π\pi, generalising the multiplicative kernel. For these kernels, a gelation transition occurs at a finite time tg∈(0,∞)t_\mathrm{g}\in (0,\infty), which can be given exactly in terms of an eigenvalue problem in finite dimensions. We prove a hydrodynamic limit for a stochastic coagulant, including a corresponding phase transition for the largest particle, and exploit a coupling to random graphs to extend analysis of the limiting process beyond the gelation time.Comment: Generalises the previous version to focus on general coagulation processes of bilinear type, without restricting to the single example of the previous version. The previous results are mentioned as motivation, and all results of the previous version can be obtained from this more general versio

    SDSS J210014.12+004446.0 - dwarf nova with negative and positive superhumps

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    We report the results of 67h of CCD photometry of the recently discovered dwarf nova SDSS J210014.12+004446.0. The data were obtained on 24 nights spanning a month. During this time we observed four ordinary outbursts lasting about 2-3 days and reaching an amplitude of ~1.7 mag. On all nights our light curve revealed persistent modulation with the stable period of 0.081088(3) days. These humps were already observed on one night by Tramposch et al. (2005), who additionally observed superhumps during a superoutburst. Remarkably, from scant evidence at their disposal they were able to discern them as negative and positive (common) superhumps, respectively. Our period in quiescence clearly different from their superhump period confirmed this. Our discovery of an additional modulation, attributed by us to the orbital wave, completes the overall picture. Lack of superhumps in our data indicates that all eruptions we observed were ordinary outbursts. The earlier observation of the superhumps combined with the presence of the ordinary outbursts in our data enables classification of SDSS J2100 as an active SU UMa dwarf nova. Additionally, we have promoted SDSS J2100 to the group of cataclysmic variables exhibiting three periodic modulations of light from their accretion discs. We updated available information on positive and negative superhumps and thus provided enhanced evidence that their properties are strongly correlated mutually as well as with the orbital period. By recourse to these relations we were able to remove an alias ambiguity and to identify the orbital period of SDSS J2100 of 0.083304(6) days. SDSS J21000 is only third SU UMa dwarf nova showing both positive and negative superhumps. Their respective period excess and deficit equal to 4.99(3)% and -2.660(8)%, yielding the mass ratio q=0.24.Comment: 10 pages, 9 figures, accepted for publication in MNRA

    On the admissibility of unboundedness properties of forced deterministic and stochastic sublinear Volterra summation equations

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    In this paper we consider unbounded solutions of perturbed convolution Volterra summation equations. The equations studied are asymptotically sublinear, in the sense that the state--dependence in the summation is of smaller than linear order for large absolute values of the state. When the perturbation term is unbounded, it is elementary to show that solutions are also. The main results of the paper are mostly of the following form: the solution has an additional unboundedness property UU if and only if the perturbation has property UU. Examples of property UU include monotone growth, monotone growth with fluctuation, fluctuation on R\mathbb{R} without growth, existence of time averages. We also study the connection between the times at which the perturbation and solution reach their running maximum, and the connection between the size of signed and unsigned running maxima of the solution and forcing term.Comment: 45 page
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