994 resultados para Green-Kubo Theory


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Republicanism and in particular the civic republican tradition is not often one that one finds in discusions and debates within green political theory. It is interesting to note the relative lack of engagement between republican political theory and green political theory, unlike for example the research one can find on the relationship between green politics/political theory and liberalism, socialism and feminism. This is remarkable, given, as I hope to establish in this paper, the large areas of overlap between both, and in particular the compatibility of republican ideas and positions with key priciples and objectives of green theory, paricularly in relation to active citizenship, the centrality of recognising vulnerability and a commitment to liberty (as non-domination) and pluralism as key components of the transition to a more sustainable society.

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Ecologism or green political theory is the most recent of schools of political thinking. On the one hand, it focuses on issues that are extremely old in politics and philosophical inquiry – such as the relationship between the human and nonhuman worlds, the moral status of animals, what is the ‘good life’, and the ethical and political regulation of technological innovation. Yet on the other, it is also characterised as dealing with some specifically contemporary issues such as the economic and political implications of climate change, peak oil, overconsumption, resource competition and conflicts, and rising levels of global and national inequalities. It is also an extremely broad school of political thought covering a wide variety of concerns, contains a number of distinct sub-schools of green thought (here sharing a similarity with other political ideologies) and combines normative and empirical scientific elements in a unique manner making it distinctive from other political ideologies.

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The incorporation of graphitic compounds such as carbon nanotubes (CNTs) and graphene into nano-electronic device packaging holds much promise for waste heat management given their high thermal conductivities. However, as these graphitic materials must be used in together with other semiconductor/insulator materials, it is not known how thermal transport is affected by the interaction. Using different simulation techniques, in this thesis, we evaluate the thermal transport properties - thermal boundary conductance (TBC) and thermal conductivity - of CNTs and single-layer graphene in contact with an amorphous SiO2 (a-SiO2) substrate. First, the theoretical methodologies and concepts used in our simulations are presented. In particular, two concepts are described in detail as they are necessary for the understanding of the subsequent chapters. The first is the linear response Green-Kubo (GK) theory of thermal boundary conductance (TBC), which we develop in this thesis, and the second is the spectral energy density method, which we use to directly compute the phonon lifetimes and thermal transport coefficients. After we set the conceptual foundations, the TBC of the CNT-SiO2 interface is computed using non- equilibrium molecular dynamics (MD) simulations and the new Green-Kubo method that we have developed. Its dependence on temperature, the strength of the interaction with the substrate, and tube diameter are evaluated. To gain further insight into the phonon dynamics in supported CNTs, the scattering rates are computed using the spectral energy density (SED) method. With this method, we are able to distinguish the different scattering mechanisms (boundary and CNT-substrate phonon-phonon) and rates. The phonon lifetimes in supported CNTs are found to be reduced by contact with the substrate and we use that lifetime reduction to determine the change in CNT thermal conductivity. Next, we examine thermal transport in graphene supported on SiO2. The phonon contribution to the TBC of the graphene-SiO2 interface is computed from MD simulations and found to agree well with experimentally measured values. We derive the theory of remote phonon scattering of graphene electrons and compute the heat transfer coefficient dependence on doping level and temperature. The thermal boundary conductance from remote phonon scattering is found to be an order of magnitude smaller than that of the phonon contribution. The in-plane thermal conductivity of supported graphene is calculated from MD simulations. The experimentally measured order of magnitude reduction in thermal conductivity is reproduced in our simulations. We show that this reduction is due to the damping of the flexural (ZA) modes. By varying the interaction between graphene and the substrate, the ZA modes hybridize with the substrate Rayleigh modes and the dispersion of the hybridized modes is found to linearize in the strong coupling limit, leading to an increased thermal conductance in the composite structure.

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The goal of this article is to propose the model of green human resource initiatives adoption. Based on innovation management and psychology literatures, attitude, pressure and controllability are key drivers for organizational change. Data were collected from 210 organizations in Australia. Results indicated that attitude, pressure and controllability significantly influenced the firms’ adoption of green HR initiatives. Attitude and resource availability especially had greater impacts than pressure. Limitation, implications and future researches are also outlined.

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This paper traces aspects of the development of a ‘green’ criminology. It starts with personal reflections and then describes the emergence of explicit statements of a green criminological perspective. Initially these statements were independently voiced, in different parts of the world but they reflected shared concerns. These works have found unification as a ‘green’, ‘eco-global’ or ‘conservation’ criminology. The paper reviews the classifications available when talking about not only legally-defined crimes but also legally perpetrated harms, as well as typologies of such harms and crimes. It then looks at the integration of ‘green’ and ‘traditional’ criminological thinking before briefly exploring four dimensions of concern for today and the future.

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A formal way of deriving fluctuation-correlation relations in dense sheared granular media, starting with the Enskog approximation for the collision integral in the Chapman-Enskog theory, is discussed. The correlation correction to the viscosity is obtained using the ring-kinetic equation, in terms of the correlations in the hydrodynamic modes of the linearised Enskog equation. It is shown that the Green-Kubo formula for the shear viscosity emerges from the two-body correlation function obtained from the ring-kinetic equation.

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Purpose This chapter explores the ideas of Alasdair MacIntyre and Vaclav Havel and what these two thinkers can contribute to green political theory. Design/methodology/approach This chapter includes examination of some of the key works of Havel and MacIntyre and analysis of these works from the point of view of green political theory. Findings The section ‘Havel and the Imperative to “Live in Truth”: Dissent and Green Politics’ explores Havel’s thought with a particular emphasis on his ethicised notion of political action and critique (‘living in truth’) and his focus on the centrality of dissent (both intellectually and in practice) as central to political critique and action. The section ‘MacIntyre as a Green Thinker: Vulnerability in Political and Moral Theory’ offers an overview of MacIntyre interpreted as a putative green thinker, with a particular emphasis on his ideas of dependence and vulnerability. The Conclusion attempts to draw some common themes together from both thinkers in terms of what they have to offer contemporary green political thought. Research limitations/implications What is presented here is introductory, ground clearing and therefore necessarily suggestive (as well as under-developed). That is, it is the start of a new area of exploration rather than an analysis based on any exhaustive and comprehensive knowledge of both thinkers. Practical implications This chapter offers some initial lines of exploration for scholars interested in the overlap between green thinking and the work of Havel and MacIntyre. Originality/value This is the first exploration of the connections between the works of Havel and MacIntyre and green political theory.

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This chapter presents the fundamentals of “green” marketing by drawing on traditional marketing theory as well as researchfocused on green marketing context. It discusses five critical areas in green marketing. The first critical area stems from green marketingtheory and practice that examines the logic for reducing the environmental impact of value creation and exchange. The second criticalarea highlights green marketing strategy that focuses on achieving organizational goals in ways that can reduce or eliminate negativeimpacts on the natural environment. The third critical area examines the green marketing mix that accounts for green products, greendistribution, green pricing, and green promotion. By using traditional marketing concepts, the chapter identifies how the entiremarketing mix elements should consistently provide a complete green product offering. Green products and processes need to beresearched, designed, and manufactured to include environmentally safe ingredients and components. Products need to be strategicallypriced to reflect their green values, distributed in the green chain channels and displayed effectively to highlight their status, and accuratelycommunicated to consumers and stakeholders. The fourth critical area illustrates governance and control. It shows how theholistic transformation toward greening the organization requires organizational culture change to gain support within and outside thefirm to ensure environmental issues are appropriately considered. These can be assessed by using existing management mechanisms,such as environmental management systems and/or triple bottom line management, which ensure best practice and continuousimprovements to occur. Lastly, the chapter discusses the future of green marketing and the direction that businesses need to take if theyseek to be sustainable.

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The effect of correlations on the viscosity of a dilute sheared inelastic fluid is analyzed using the ring-kinetic equation for the two-particle correlation function. The leading-order contribution to the stress in an expansion in epsilon=(1-e)(1/2) is calculated, and it is shown that the leading-order viscosity is identical to that obtained from the Green-Kubo formula, provided the stress autocorrelation function in a sheared steady state is used in the Green-Kubo formula. A systemmatic extension of this to higher orders is also formulated, and the higher-order contributions to the stress from the ring-kinetic equation are determined in terms of the terms in the Chapman-Enskog solution for the Boltzmann equation. The series is resummed analytically to obtain a renormalized stress equation. The most dominant contributions to the two-particle correlation function are products of the eigenvectors of the conserved hydrodynamic modes of the two correlated particles. In Part I, it was shown that the long-time tails of the velocity autocorrelation function are not present in a sheared fluid. Using those results, we show that correlations do not cause a divergence in the transport coefficients; the viscosity is not divergent in two dimensions, and the Burnett coefficients are not divergent in three dimensions. The equations for three-particle and higher correlations are analyzed diagrammatically. It is found that the contributions due to the three-particle and higher correlation functions to the renormalized viscosity are smaller than those due to the two-particle distribution function in the limit epsilon -> 0. This implies that the most dominant correlation effects are due to the two-particle correlations.

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We have applied the Green function theory in GW approximation to calculate the quasiparticle energies for semiconductors Si and GaAs. Good agreements of the calculated excitation energies and fundamental energy gaps with the experimental band structures were achieved. We obtained the calculated fundamental gaps of Si and GaAs to be 1.22 and 1.42 eV in comparison to the experimental values of 1.17 and 1.52 eV, respectively. Ab initio pseudopotential method has been used to generate basis wavefunctions and charge densities for calculating dielectric matrix elements and electron self-energies.

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We successfully applied the Green function theory in GW approximation to calculate the quasiparticle energies for semiconductors Si and GaAs. Ab initio pseudopotential method was adopted to generate basis wavefunctions and charge densities for calculating dielectric matrix elements and electron self-energies. To evaluate dynamical effects of screened interaction, GPP model was utilized to extend dieletric matrix elements from static results to finite frequencies. We give a full account of the theoretical background and the technical details for the first principle pseudopotential calculations of quasiparticle energies in semiconductors and insulators. Careful analyses are given for the effective and accurate evaluations of dielectric matrix elements and quasiparticle self-energies by using the symmetry properties of basis wavefunctions and eigenenergies. Good agreements between the calculated excitation energies and fundamental energy gaps and the experimental band structures were achieved.

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