992 resultados para OPEN BOUNDARIES
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The A(n-1)((1)) trigonometric vertex model with generic non-diagonal boundaries is studied. The double-row transfer matrix of the model is diagonalized by algebraic Bethe ansatz method in terms of the intertwiner and the corresponding face-vertex relation. The eigenvalues and the corresponding Bethe ansatz equations are obtained.
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We present a study of the evaporation dynamics of a substance undergoing a coarsening process. The system is modeled by the Cahn-Hilliard equation with absorbing boundaries. We have found that the dynamics, although of a diffusive nature, is much slower than the usual one without coarsening. Analytical and simulation results are in reasonable agreement.
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We present a study of the evaporation dynamics of a substance undergoing a coarsening process. The system is modeled by the Cahn-Hilliard equation with absorbing boundaries. We have found that the dynamics, although of a diffusive nature, is much slower than the usual one without coarsening. Analytical and simulation results are in reasonable agreement.
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The XXZ Gaudin model with generic integrable boundaries specified by generic non-diagonal K-matrices is studied. The commuting families of Gaudin operators are diagonalized by the algebraic Bethe ansatz method. The eigenvalues and the corresponding Bethe ansatz equations are obtained. (C) 2004 Elsevier B.V. All rights reserved.
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The A(n-1) Gaudin model with integrable boundaries specified by non-diagonal K-matrices is studied. The commuting families of Gaudin operators are diagonalized by the algebraic Bethe ansatz method. The eigenvalues and the corresponding Bethe ansatz equations are obtained. (c) 2005 Elsevier B.V. All rights reserved.
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We present a reformulation of the hairy-probe method for introducing electronic open boundaries that is appropriate for steady-state calculations involving nonorthogonal atomic basis sets. As a check on the correctness of the method we investigate a perfect atomic wire of Cu atoms and a perfect nonorthogonal chain of H atoms. For both atom chains we find that the conductance has a value of exactly one quantum unit and that this is rather insensitive to the strength of coupling of the probes to the system, provided values of the coupling are of the same order as the mean interlevel spacing of the system without probes. For the Cu atom chain we find in addition that away from the regions with probes attached, the potential in the wire is uniform, while within them it follows a predicted exponential variation with position. We then apply the method to an initial investigation of the suitability of graphene as a contact material for molecular electronics. We perform calculations on a carbon nanoribbon to determine the correct coupling strength of the probes to the graphene and obtain a conductance of about two quantum units corresponding to two bands crossing the Fermi surface. We then compute the current through a benzene molecule attached to two graphene contacts and find only a very weak current because of the disruption of the π conjugation by the covalent bond between the benzene and the graphene. In all cases we find that very strong or weak probe couplings suppress the current.
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We study the exact solution of an N-state vertex model based on the representation of the U(q)[SU(2)] algebra at roots of unity with diagonal open boundaries. We find that the respective reflection equation provides us one general class of diagonal K-matrices having one free-parameter. We determine the eigenvalues of the double-row transfer matrix and the respective Bethe ansatz equation within the algebraic Bethe ansatz framework. The structure of the Bethe ansatz equation combine a pseudomomenta function depending on a free-parameter with scattering phase-shifts that are fixed by the roots of unity and boundary variables. (C) 2010 Elsevier B.V. All rights reserved.
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We consider the time evolution of an exactly solvable cellular automaton with random initial conditions both in the large-scale hydrodynamic limit and on the microscopic level. This model is a version of the totally asymmetric simple exclusion process with sublattice parallel update and thus may serve as a model for studying traffic jams in systems of self-driven particles. We study the emergence of shocks from the microscopic dynamics of the model. In particular, we introduce shock measures whose time evolution we can compute explicitly, both in the thermodynamic limit and for open boundaries where a boundary-induced phase transition driven by the motion of a shock occurs. The motion of the shock, which results from the collective dynamics of the exclusion particles, is a random walk with an internal degree of freedom that determines the jump direction. This type of hopping dynamics is reminiscent of some transport phenomena in biological systems.
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Chains of interacting non-Abelian anyons with local interactions invariant under the action of the Drinfeld double of the dihedral group D-3 are constructed. Formulated as a spin chain the Hamiltonians are generated from commuting transfer matrices of an integrable vertex model for periodic and braided as well as open boundaries. A different anyonic model with the same local Hamiltonian is obtained within the fusion path formulation. This model is shown to be related to an integrable fusion interaction round the face model. Bulk and surface properties of the anyon chain are computed from the Bethe equations for the spin chain. The low-energy effective theories and operator content of the models (in both the spin chain and fusion path formulation) are identified from analytical and numerical studies of the finite-size spectra. For all boundary conditions considered the continuum theory is found to be a product of two conformal field theories. Depending on the coupling constants the factors can be a Z(4) parafermion or a M-(5,M-6) minimal model.
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Shipping List Date: 09/05/2006
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Taking a realist view that law is one form of politics, this dissertation studies the roles of citizens and organizations in mobilizing the law to request government agencies to disclose environmental information in China, and during this process, how the socio-legal field interacts with the political-legal sphere, and what changes have been brought about during their interactions. This work takes a socio-legal approach and applies methodologies of social science and legal analysis. It aims to understand the paradox of why and how citizens and entities have been invoking the law to access environmental information despite the fact that various obstacles exist and the effectiveness of the new mechanism of environmental information disclosure still remains low. The study is largely based on the 28 cases and eight surveys of environmental information disclosure requests collected by the author. The cases and surveys analysed in this dissertation all occurred between May 2008, when the OGI Regulations and the OEI Measures came into effect, and August 2012 when the case collection was completed. The findings of this study have shown that by invoking the rules of law made by the authorities to demand government agencies disclosing environmental information, the public, including citizens, organizations, law firms, and the media, have strategically created a repercussive pressure upon the authorities to act according to the law. While it is a top-down process that has established the mechanism of open government information in China, it is indeed the bottom-up activism of the public that makes it work. Citizens and organizations’ use of legal tactics to push government agencies to disclose environmental information have formed not only an end of accessing the information but more a means of making government agencies accountable to their legal obligations. Law has thus played a pivotal role in enabling citizen participation in the political process. Against the current situation in China that political campaigns, or politicization, from general election to collective actions, especially contentious actions, are still restrained or even repressed by the government, legal mobilization, or judicialization, that citizens and organizations use legal tactics to demand their rights and push government agencies to enforce the law, become de facto an alternative of political participation. During this process, legal actions have helped to strengthen the civil society, make government agencies act according to law, push back the political boundaries, and induce changes in the relationship between the state and the public. In the field of environmental information disclosure, citizens and organizations have formed a bottom-up social activism, though limited in scope, using the language of law, creating progressive social, legal and political changes. This study emphasizes that it is partial and incomplete to understand China’s transition only from the top-down policy-making and government administration; it is also important to observe it from the bottom-up perspective that in a realistic view law can be part of politics and legal mobilization, even when utterly apolitical, can help to achieve political aims as well. This study of legal mobilization in the field of environmental information disclosure also helps us to better understand the function of law: law is not only a tool for the authorities to regulate and control, but inevitably also a weapon for the public to demand government agencies to work towards their obligations stipulated by the laws issued by themselves.
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Open innovation paradigm states that the boundaries of the firm have become permeable, allowing knowledge to flow inwards and outwards to accelerate internal innovations and take unused knowledge to the external environment; respectively. The successful implementation of open innovation practices in firms like Procter & Gamble, IBM, and Xerox, among others; suggest that it is a sustainable trend which could provide basis for achieving competitive advantage. However, implementing open innovation could be a complex process which involves several domains of management; and whose term, classification, and practices have not totally been agreed upon. Thus, with many possible ways to address open innovation, the following research question was formulated: How could Ericsson LMF assess which open innovation mode to select depending on the attributes of the project at hand? The research followed the constructive research approach which has the following steps: find a practical relevant problem, obtain general understanding of the topic, innovate the solution, demonstrate the solution works, show theoretical contributions, and examine the scope of applicability of the solution. The research involved three phases of data collection and analysis: Extensive literature review of open innovation, strategy, business model, innovation, and knowledge management; direct observation of the environment of the case company through participative observation; and semi-structured interviews based of six cases involving multiple and heterogeneous open innovation initiatives. Results from the cases suggest that the selection of modes depend on multiple reasons, with a stronger influence of factors related to strategy, business models, and resources gaps. Based on these and others factors found in the literature review and observations; it was possible to construct a model that supports approaching open innovation. The model integrates perspectives from multiple domains of the literature review, observations inside the case company, and factors from the six open innovation cases. It provides steps, guidelines, and tools to approach open innovation and assess the selection of modes. Measuring the impact of open innovation could take years; thus, implementing and testing entirely the model was not possible due time limitation. Nevertheless, it was possible to validate the core elements of the model with empirical data gathered from the cases. In addition to constructing the model, this research contributed to the literature by increasing the understanding of open innovation, providing suggestions to the case company, and proposing future steps.
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This article discusses the relationship between digital humanities and disciplinary boundaries in the last decade, primarily in the context of the national project Synergies. It offers first an overview of Synergies as a concrete example of the way technological change impacts the very notion of disciplines by trying to create a platform that was interdisciplinary by nature, then discusses the creation of a new Digital Humanities centre in Québec—Le Centre de recherche interuniversitaire sur les humanités numériques – and the ways it was conceived as encompassing a range of disciplinary approach.