655 research outputs found

    The potential of integrating E-participation in planning support systems

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    The increasing complexity of spatial planning issues and pressure from citizens to takepart in designing and deciding on spatial plans result in a need for improved methods to aidcommunication between governmental actors and citizens. These developments put high demands onparticipatory Planning Support Systems (PSS); instruments that can aid planners in doing theirplanning tasks. By using the accessibility of the internet, e-participation offers opportunities as a PSS.Although many advantages are attributed to participatory PSS, its use in the planning practice remainsmarginal until now. It is argued here that this is partly caused by the lack of empirical studies thatdemonstrate potential benefits and problems when applying PSS. This paper provides guidelines fororganizations that contemplate on using a participatory PSS. In order to do so, a framework isdeveloped, identifying obstacles that could block effective participation in a PSS. Three planningprocesses are evaluated to investigate the importance of these obstacles. It is demonstrated that,although e-participation has potential as PSS, the lack of political will blocks effective participationand a more profound link between the citizen input and the decision-making is neede

    New connection formulae for some q-orthogonal polynomials in q-Askey scheme

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    New nonlinear connection formulae of the q-orthogonal polynomials, such continuous q-Laguerre, continuous big q-Hermite, q-Meixner-Pollaczek and q-Gegenbauer polynomials, in terms of their respective classical analogues are obtained using a special realization of the q-exponential function as infinite multiplicative series of ordinary exponential function

    Interpolation of SUSY quantum mechanics

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    Interpolation of two adjacent Hamiltonians in SUSY quantum mechanics Hs=(1s)AA+sAAH_s=(1-s)A^{\dagger}A + sAA^{\dagger}, 0s10\le s\le 1 is discussed together with related operators. For a wide variety of shape-invariant degree one quantum mechanics and their `discrete' counterparts, the interpolation Hamiltonian is also shape-invariant, that is it takes the same form as the original Hamiltonian with shifted coupling constant(s).Comment: 18 page

    A study on the fourth q-Painlev\'e equation

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    A q-difference analogue of the fourth Painlev\'e equation is proposed. Its symmetry structure and some particular solutions are investigated.Comment: 18 page

    Quantum state transfer in spin chains with q-deformed interaction terms

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    We study the time evolution of a single spin excitation state in certain linear spin chains, as a model for quantum communication. Some years ago it was discovered that when the spin chain data (the nearest neighbour interaction strengths and the magnetic field strengths) are related to the Jacobi matrix entries of Krawtchouk polynomials or dual Hahn polynomials, so-called perfect state transfer takes place. The extension of these ideas to other types of discrete orthogonal polynomials did not lead to new models with perfect state transfer, but did allow more insight in the general computation of the correlation function. In the present paper, we extend the study to discrete orthogonal polynomials of q-hypergeometric type. A remarkable result is a new analytic model where perfect state transfer is achieved: this is when the spin chain data are related to the Jacobi matrix of q-Krawtchouk polynomials. The other cases studied here (affine q-Krawtchouk polynomials, quantum q-Krawtchouk polynomials, dual q-Krawtchouk polynomials, q-Hahn polynomials, dual q-Hahn polynomials and q-Racah polynomials) do not give rise to models with perfect state transfer. However, the computation of the correlation function itself is quite interesting, leading to advanced q-series manipulations

    Epicycles and Poincar\'{e} Resonances in General Relativity

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    The method of geodesic deviations provides analytic approximations to geodesics in arbitrary background space-times. As such the method is a useful tool in many practical situations. In this note we point out some subtleties in the application of the method related to secular motions, in first as well as in higher order. In particular we work out the general second-order contribution to bound orbits in Schwarzschild space-time and show that it provides very good analytical results all the way up to the innermost stable circular orbit.Comment: 24 pages, 4 figure

    Mathematical Structure of Relativistic Coulomb Integrals

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    We show that the diagonal matrix elements ,, where OO =1,β,iαnβ={1,\beta,i\mathbf{\alpha n}\beta} are the standard Dirac matrix operators and the angular brackets denote the quantum-mechanical average for the relativistic Coulomb problem, may be considered as difference analogs of the radial wave functions. Such structure provides an independent way of obtaining closed forms of these matrix elements by elementary methods of the theory of difference equations without explicit evaluation of the integrals. Three-term recurrence relations for each of these expectation values are derived as a by-product. Transformation formulas for the corresponding generalized hypergeometric series are discussed.Comment: 13 pages, no figure

    More on the q-oscillator algebra and q-orthogonal polynomials

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    Properties of certain qq-orthogonal polynomials are connected to the qq-oscillator algebra. The Wall and qq-Laguerre polynomials are shown to arise as matrix elements of qq-exponentials of the generators in a representation of this algebra. A realization is presented where the continuous qq-Hermite polynomials form a basis of the representation space. Various identities are interpreted within this model. In particular, the connection formula between the continuous big qq-Hermite polynomials and the continuous qq-Hermite polynomials is thus obtained, and two generating functions for these last polynomials are algebraically derived
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