25 research outputs found
M. Gaster, Literatura populara romana. Cu un apendice : Voroava garamantilor cu Alexandru Machedon de Nicolae Costin. 1883
No full textM. Gaster, Literatura populara romana. Cu un apendice : Voroava garamantilor cu Alexandru Machedon de Nicolae Costin. 1883. In: Romania, tome 14 n°53, 1885. pp. 149-155
M. Gaster, Literatura populara romana. Cu un apendice : Voroava garamantilor cu Alexandru Machedon de Nicolae Costin. 1883
No full textM. Gaster, Literatura populara romana. Cu un apendice : Voroava garamantilor cu Alexandru Machedon de Nicolae Costin. 1883. In: Romania, tome 14 n°53, 1885. pp. 149-155
Second-order corrections to mean field evolution of weakly interacting Bosons. II
No full textAbstractWe study the evolution of an N-body weakly interacting system of Bosons. Our work forms an extension of our previous paper Grillakis, Machedon, and Margetis (2010) [13], in which we derived a second-order correction to a mean-field evolution law for coherent states in the presence of small interaction potential. Here, we remove the assumption of smallness of the interaction potential and prove global existence of solutions to the equation for the second-order correction. This implies an improved Fock-space estimate for our approximation of the N-body state
APPLICATION OF DISPERSIVE PDE TECHNIQUES TO THE STUDIES OF THE TIME-DEPENDENT HARTREE-FOCK-BOGOLIUBOV SYSTEM FOR BOSONS
No full textThe thesis provides rigorous quantitative analyses for studying quantum fluctuations of a
non-relativistic Bose gas about a Bose-Einstein condensate. In recent years, the dynamics of the condensate and the excitations of a Bose gas was shown to be well approximated by the quasifree dynamics with governing equations given by a system of coupled nonlinear dispersive PDEs called the time-dependent Hartree-Fock-Bogoliubov (HFB) system (c.f. Grillakis and Machedon, J. Fix. Point Theory A., (2013), Grillakis and Machedon, Comm. PDEs, (2017), Bach et al. in arXiv:1602.05171v2, (2018), Benedikter et al., Ann. Henri Poincare, (2018)). However, both the quantitative and qualitative analysis of the time-dependent HFB system are still in their early stages of development. Thus, the primary purposes of the thesis are to further the development of some analytic tools necessary for studying the time-dependent HFB system and use these effective equations to provide quantitative estimates for the true dynamics of the Bose gas at absolute zero temperature in Fock space norm.
The thesis comprises the entirety of the author's current and past projects on the time-dependent HFB system. Each project falls into one or more of two categories: studying the local or global well-posedness of the time-dependent HFB system, or obtaining global-in-time Fock space estimates for the error terms of the quasifree approximation to the dynamics of a system of interacting bosons. In the former category, the author employs techniques of dispersive PDE theory developed in the past three decades along with classical methods of harmonic analysis to study lower regularity solutions to the time-dependent HFB system. The lower regularity well-posedness of solutions for the time-dependent HFB system is necessary for studying norm approximation of the dynamics of a dilute Bose gas with strong interactions. In the latter category, we prove global a-priori estimates for the solutions to the HFB system and use them to obtain estimates for the error terms of the Fock space approximation
Your Home’s Check-In Gate: Spatial Planning Strategies for the Urban Integration of the Development Driven by Amsterdam Schiphol Airport
No full textThis graduation thesis tackles the issue of airport-driven urban development in the Amsterdam Metropolitan Area context. Initially planned outside of cities for security and pollution reasons airports are now attracting urban development in their proximity. This development consisting of hotels, office spaces or congress centres is driven by the benefits of a location providing a fast connection to an airport with a large variety of flight destinations. This phenomena is linked to a time based competition business model in which the speed with which companies reach their world spread customer base is vital for their performance (Kasarda, 2000). Through the large flows of people and goods that they attract airports are becoming regional nodes of activity in their city regions. Multiple authors indicate the need for the development of new conceptual frameworks that would help better understand the complex urban interactions triggered by airports on a regional scale (Freestone and Baker, 2011, Salewski et al., 2012, Schaafsma, 2009, Schlaak, 2009, Knippenberger, 2010). Through this thesis I am proposing an alternative spatial development strategy for the area between Schiphol Airport and Amsterdam. The strategy aims to integrate the airport related urban networks in a regional vision which takes into consideration spatial, demographic and economic trends specific to the Amsterdam Metropolitan Area. Moreover the strategy aims to provide solutions for the local urban integration of airport related business parks. My vision for the area is to develop Amsterdamse Bos as a metropolitan park with an urban edge providing a living and working environment in an international context. Existing spatial planning models of airport-driven urban development are not yet sufficiently developed. I therefore chose to use network urbanism theories in order to explain and propose future development strategies on a regional and local scale. The thesis ends with an evaluation of the proposed strategy and of the suitability of a network urbanism approach within this context.Spatial Planning and Strategy ChairUrbanismArchitectur
A New Proof of Global Existence for the Dirac Klein–Gordon Equations in One Space Dimension
No full textAbstractUsing a method of S. Klainerman and M. Machedon, we give a new proof of global existence for the coupled Dirac and Klein–Gordon equations in one space dimension
Pair excitations and the mean field approximation of interacting Bosons
No full textAbstract. In our previous wor
