Search results for "ansat"
showing 10 items of 224 documents
Interactions between Climate Change and Infrastructure Projects in Changing Water Resources: An Ethnobiological Perspective from the Daasanach, Kenya
2021
The fast and widespread environmental changes that have intensified in the last decades are bringing disproportionate impacts to Indigenous Peoples and Local Communities. Changes that affect water resources are particularly relevant for subsistence-based peoples, many of whom already suffer from constraints regarding reliable access to safe water. Particularly in areas where water is scarce, climate change is expected to amplify existing stresses in water availability, which are also exacerbated by multiple socioeconomic drivers. In this paper, we look into the local perceptions of environmental change expressed by the Daasanach people of northern Kenya, where the impacts of climate change …
Coarse-grained models of double-stranded DNA based on experimentally determined knotting probabilities
2018
Abstract To accurately model double-stranded DNA in a manner that is computationally efficient, coarse-grained models of DNA are introduced, where model parameters are selected by fitting the spectrum of observable DNA knots: We develop a general method to fit free parameters of coarse-grained chain models by comparing experimentally obtained knotting probabilities of short DNA chains to knotting probabilities that are computed in Monte Carlo simulations, resulting in coarse-grained DNA models which are tailored to reflect DNA topology in the best possible way. The method is exemplified by fitting ideal chain models as well as a bead-spring model with excluded volume interactions, to model …
Separated children & forbidden roots : removals of part-indigenous children as part of Australia's assimilation policy in the 1950s-1960s
2013
1950-ja 1960-luvuilla Australiassa oli kaksi merkittävää poliittista käytäntöä, joilla oli merkittävä vaikutus maan alkuperäisväestöön nimittäin assimilaatio sekä osittain valkoista alkuperää olevien aboriginaalilasten pakkohuostaanotot. Tutkielma käsittelee Australian assimilaatio politiikkaa, sen keinoja ja taustoja sekä varsinkin sen yhteyttä aboriginaalilasten pakkohuostaanottoihin. Jo 1800-luvulta lähtien Australiassa oli ollut vallalla käytäntö erottaa aboriginaalilapsia vanhemmistaan ja yhteisöistään koulutukset, parempien elinolojen tai kristillisen lähetystyön velvoittamana. Heistä koulutettiin halpaa, kristillistä työvoimaa valloitetuille alueille. 1920-luvulta alkanut osittain va…
Anulación del privacy shield en las transferencias internacionales de datos : ¿presenciamos un desplazamiento fáctico de la responsabilidad?
2021
This study provides a comprehensive analysis of international transfers of personal data to third countries or international organizations due to new privacy regulation. More specifically, it analyzes the effects on this regulatory scheme of the annulment of the Privacy Shield in the transatlantic information movements between the European Union and the United States and how this implies, in fact, a transfer of responsibility to the controller
A modified ansatz for explicitly correlated coupled-cluster wave functions that is suitable for response theory
2009
A modified ansatz for explicitly correlated coupled-cluster wave functions with a single correlation factor is set forward. It is based on the fixed amplitude ansatz of Ten-no [Chem. Phys. Lett. 398, 56 (2004)] to which an extra term is added that allows for the explicitly correlated description of singly excited configurations. The new approach has been implemented for coupled-cluster singles and doubles with the aid of automated techniques. Numerical results are presented for vertical excitation energies, and ground and excited state equilibrium distances and harmonic frequencies of diatomics. The new approach is shown to provide a nearly unbiased description of ground and predominantly s…
LAS REFORMAS INSTITUCIONALES COMO MEDIO DE FORTALECIMIENTO DE LA DEMOCRACIA, Y COMO COMBATE CONTRA LA CORRUPCIÓN Y LA IMPUNIDAD: UNA CONTRIBUCIÓN PAR…
2019
Es común ver regímenes dictatoriales o conflictos armados, o ambos, repetidos en el mismo país. Esto nos invita a iniciar una reflexión sobre la necesidad de demostrar que la implementación y puesta en marcha de una agenda de "transición política" debe centrarse en la seriedad y en el tipo de reformas institucionales a adoptar, ya que se trata de medidas importantes y elementales para garantizar el fortalecimiento del Estado de Derecho, la reconstrucción del Estado, la reconciliación nacional, la consolidación democrática y las respectivas instituciones, que permitan superar el legado autoritario o el conflicto armado que ha vivido una sociedad. Es evidente que cuando hablamos del país que …
Compact two-electron wave function for bond dissociation and Van der Waals interactions: A natural amplitude assessment
2014
Electron correlations in molecules can be divided in short range dynamical correlations, long range Van der Waals type interactions and near degeneracy static correlations. In this work we analyze for a one-dimensional model of a two-electron system how these three types of correlations can be incorporated in a simple wave function of restricted functional form consisting of an orbital product multiplied by a single correlation function $f(r_{12})$ depending on the interelectronic distance $r_{12}$. Since the three types of correlations mentioned lead to different signatures in terms of the natural orbital (NO) amplitudes in two-electron systems we make an analysis of the wave function in t…
Driven Bose-Hubbard Model with a Parametrically Modulated Harmonic Trap
2016
We investigate a one-dimensional Bose–Hubbard model in a parametrically driven global harmonic trap. The delicate interplay of both the local interaction of the atoms in the lattice and the driving of the global trap allows us to control the dynamical stability of the trapped quantum many-body state. The impact of the atomic interaction on the dynamical stability of the driven quantum many-body state is revealed in the regime of weak interaction by analyzing a discretized Gross–Pitaevskii equation within a Gaussian variational ansatz, yielding a Mathieu equation for the condensate width. The parametric resonance condition is shown to be modified by the atom interaction strength. In particul…
Multireference equation-of-motion coupled cluster theory.
2012
A generalization of the equation-of-motion coupled cluster theory is proposed, which is built upon a multireference parent state. This method is suitable for a number of electronic states of a system that can be described by similar active spaces, i.e., different linear combinations of the same set of active space determinants. One of the suitable states is chosen as the parent state and the dominant dynamical correlation is optimized for this state using an internally contracted multireference coupled cluster ansatz. The remaining correlation and orbital relaxation effects are obtained via an uncontracted diagonalization of the transformed Hamiltonian, Ĥ = e(-T) Ĥe(T), in a compact multire…
Derivation of coarse-grained simulation models of chlorophyll molecules in lipid bilayers for applications in light harvesting systems
2015
The correct interplay of interactions between protein, pigment and lipid molecules is highly relevant for our understanding of the association behavior of the light harvesting complex (LHCII) of green plants. To cover the relevant time and length scales in this multicomponent system, a multi-scale simulation ansatz is employed that subsequently uses a classical all atomistic (AA) model to derive a suitable coarse grained (CG) model which can be backmapped into the AA resolution, aiming for a seamless conversion between two scales. Such an approach requires a faithful description of not only the protein and lipid components, but also the interaction functions for the indispensable pigment mo…