393 research outputs found

    Metaphorical modeling concept of "energy" in the scientific discourse

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    Статья вписывается в актуальное направление исследований аспектов метафорического моделирования в научном дискурсе. На основе методологии теории концептуальной мета-форы анализируются метафорические модели, функционирующие в дискурсе природопользования. Выявлены наиболее часто встречающиеся модели метафорической концептуализации общенаучного понятия «энергия» ("ЭНЕРГИЯ - ЭТО ОБЪЕКТ", "ЭНЕРГИЯ - ЭТО ВЕЩЕСТВО", "ЭНЕРГИЯ - ЭТО ЖИВОЕ СУЩЕСТВО", "ЭНЕРГИЯ - ЭТО СОЦИАЛЬНЫЙ СУБЪЕКТ"). Энергия в текстах по природопользованию метафорически моделируется как активная, динамичная, самостоятельная, всеохватывающая субстанция, имеющая первостепенное значение в устройстве Вселенной и жизни на Земле. The article complies with up-to-date line of research in the area of modeling in scientific discourse. Based on the methodology of the theory of conceptual metaphor metaphorical model examines operating in environmental management discourse. Revealed common patterns of metaphorical conceptualization of scientific concept «energy» ("ENERGY - IS OBJECT", "ENERGY - IS SUBSTANCE", "ENERGY - IS A LIVING BEING", "ENERGY - IS A SOCIAL SUBJECT"). The energy in the texts for Nature metaphorically modeled as active, dynamic, independent, all-encompassing substance, has paramount importance in the structure of the universe and life on Earth

    A rural agricultural-sustainable energy community model and its application to Felton Valley, Australia

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    Energy and food security require a delicate balance which should not threaten or undermine community prosperity. Where it is proposed to derive energy from conventional fossil fuel resources (such as coal, shale oil, natural gas, coal seam gas) located in established rural areas, and particularly where these areas are used for productive agricultural purposes, there are often both intense community concern as well as broader questions regarding the relative social, economic and environmental costs and benefits of different land uses and, increasingly, different energy sources. The advent of mainstream renewable energy technologies means that alternative energy options may provide a viable alternative, allowing energy demand to be met without compromising existing land uses. We demonstrate how such a Sustainable Energy Rural Model can be designed to achieve a balance between the competing social goals of energy supply, agricultural production, environmental integrity and social well-being, and apply it to the Felton Valley, a highly productive and resilient farming community in eastern Australia. Research into available wind and solar resources found that Felton Valley has a number of attributes that indicate its suitability for the development of an integrated renewable energy precinct which would complement, rather than displace, existing agricultural enterprises. Modelling results suggest a potential combined annual renewable energy output from integrated wind and solar resources of 1,287 GWh/yr from peak installed capacity of 713 MW, sufficient to supply the electrical energy needs of about 160,000 homes, in combination with total biomass food production of 31,000 tonnes per annum or 146 GWh/yr of human food energy. The portfolio of renewable energy options will not only provide energy source diversity but also ensures long-term food security and regional stability. The Felton Valley model provides an example of community-led energy transformation and has potential as a pilot project for the development of smart distributed grids that would negate the need for further expansion of coal mining and coal fired power stations

    Model for Folding and Aggregation in RNA Secondary Structures

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    We study the statistical mechanics of RNA secondary structures designed to have an attraction between two different types of structures as a model system for heteropolymer aggregation. The competition between the branching entropy of the secondary structure and the energy gained by pairing drives the RNA to undergo a `temperature independent' second order phase transition from a molten to an aggregated phase'. The aggregated phase thus obtained has a macroscopically large number of contacts between different RNAs. The partition function scaling exponent for this phase is \theta ~ 1/2 and the crossover exponent of the phase transition is \nu ~ 5/3. The relevance of these calculations to the aggregation of biological molecules is discussed.Comment: Revtex, 4 pages; 3 Figures; Final published versio

    Analytical description of finite size effects for RNA secondary structures

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    The ensemble of RNA secondary structures of uniform sequences is studied analytically. We calculate the partition function for very long sequences and discuss how the cross-over length, beyond which asymptotic scaling laws apply, depends on thermodynamic parameters. For realistic choices of parameters this length can be much longer than natural RNA molecules. This has to be taken into account when applying asymptotic theory to interpret experiments or numerical results.Comment: 10 pages, 13 figures, published in Phys. Rev.

    Quasiparticle density of states in dirty high-T_c superconductors

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    We study the density of quasiparticle states of dirty d-wave superconductors. We show the existence of singular corrections to the density of states due to quantum interference effects. We then argue that the density of states actually vanishes in the localized phase as E|E| or E2E^2 depending on whether time reversal is a good symmetry or not. We verify this result for systems without time reversal symmetry in one dimension using supersymmetry techniques. This simple, instructive calculation also provides the exact universal scaling function for the density of states for the crossover from ballistic to localized behaviour in one dimension. Above two dimensions, we argue that in contrast to the conventional Anderson localization transition, the density of states has critical singularities which we calculate in a 2+ϵ2+\epsilon expansion. We discuss consequences of our results for various experiments on dirty high-TcT_c materials

    Statistical mechanics of RNA folding: a lattice approach

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    We propose a lattice model for RNA based on a self-interacting two-tolerant trail. Self-avoidance and elements of tertiary structure are taken into account. We investigate a simple version of the model in which the native state of RNA consists of just one hairpin. Using exact arguments and Monte Carlo simulations we determine the phase diagram for this case. We show that the denaturation transition is first order and can either occur directly or through an intermediate molten phase.Comment: 8 pages, 9 figure

    Quantification of the differences between quenched and annealed averaging for RNA secondary structures

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    The analytical study of disordered system is usually difficult due to the necessity to perform a quenched average over the disorder. Thus, one may resort to the easier annealed ensemble as an approximation to the quenched system. In the study of RNA secondary structures, we explicitly quantify the deviation of this approximation from the quenched ensemble by looking at the correlations between neighboring bases. This quantified deviation then allows us to propose a constrained annealed ensemble which predicts physical quantities much closer to the results of the quenched ensemble without becoming technically intractable.Comment: 9 pages, 14 figures, submitted to Phys. Rev.

    Localization-delocalization transition of disordered d-wave superconductors in class CI

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    A lattice model for disordered d-wave superconductors in class CI is reconsidered. Near the band-center, the lattice model can be described by Dirac fermions with several species, each of which yields WZW term for an effective action of the Goldstone mode. The WZW terms cancel out each other because of the four-fold symmetry of the model, which suggests that the quasiparticle states are localized. If the lattice model has, however, symmetry breaking terms which generate mass for any species of the Dirac fermions, remaining WZW term which avoids the cancellation can derive the system to a delocalized strong-coupling fixed point.Comment: 4 pages, revte

    An elementary proof of the irrationality of Tschakaloff series

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    We present a new proof of the irrationality of values of the series Tq(z)=n=0znqn(n1)/2T_q(z)=\sum_{n=0}^\infty z^nq^{-n(n-1)/2} in both qualitative and quantitative forms. The proof is based on a hypergeometric construction of rational approximations to Tq(z)T_q(z).Comment: 5 pages, AMSTe

    Weak localization of disordered quasiparticles in the mixed superconducting state

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    Starting from a random matrix model, we construct the low-energy effective field theory for the noninteracting gas of quasiparticles of a disordered superconductor in the mixed state. The theory is a nonlinear sigma model, with the order parameter field being a supermatrix whose form is determined solely on symmetry grounds. The weak localization correction to the field-axis thermal conductivity is computed for a dilute array of s-wave vortices near the lower critical field H_c1. We propose that weak localization effects, cut off at low temperatures by the Zeeman splitting, are responsible for the field dependence of the thermal conductivity seen in recent high-T_c experiments by Aubin et al.Comment: RevTex, 8 pages, 1 eps figure, typos correcte
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