Critical points of the optimal quantum control landscape: a propagator approach

Numerical and experimental realizations of quantum control are closely connected to the properties of the mapping from the control to the unitary propagator. For bilinear quantum control problems, no general results are available to fully determine when this mapping is singular or not. In this paper we give suffcient conditions, in terms of elements of the evolution semigroup, for a trajectory to be non-singular. We identify two lists of "way-points" that, when reached, ensure the non-singularity of the control trajectory. It is found that under appropriate hypotheses one of those lists does not depend on the values of the coupling operator matrix

Does Aid Really Help? The Nexus Between Development Aid and State-Society Resilience in Fragile Situations

This study aims to determine how development aid impacts state-society resilience, and how such resilience impacts aid flows in fragile situations. It particularly examines if development aid builds state-society resilience in fragile situations listed in the harmonized list of World Bank, African Development Bank, and Asian Development Bank from 2006 to 2018. Results show that development aid causes a decrease in state-society resilience, while state-society resilience causes an increase in aid flows. Aid for governance and human development weakens resilience. Better governance and peace levels curb aid flows, while higher human development levels boost aid flows. Economic growth is neither relevant to resilience levels nor aid flows. This study highlights the strong causal link between aid for governance and human development and state-society resilience. Results show that aid hurts a fragile situation but not too painfully, and that fragility is mainly attributed to violent conflict, ethnic fractionalization, and natural disasters. The study concludes that the slight negative impact of aid can be reversed through altering the development approach from hierarchical to concentric. As an alternative to the hierarchical model of development, where one intervention progresses from one stage to another, a concentric model is proposed, where governance and human development are at the core, which can create a ripple effect to sustainable peace and economic growth. Targeted assistance is therefore needed, which is to strengthen governance by improving public policies and institutions, and enhancing human development by empowering the society to collaborate with the state in achieving sustainable development goals

Retrato del autor de la Historia Augusta

Treballs Finals de Grau en Història, Facultat de Geografia i Història, Universitat de Barcelona, Curs: 2013-2014, Tutor: Ignasi Garcés EstallóSi bien la H.A. posee, oculta entre la ficción, información a menudo indispensable dada la ausencia de otras fuentes primarias para algunos episodios históricos, también es en sí misma un objeto de estudio de la época en que fue escrita y del ambiente del autor. La intención de este trabajo gira alrededor de su anónimo autor, no hasta el punto de darle nombre, pero sí de moldear un retrato caracterológico a partir únicamente de su obra

Respuesta inmune de las aves y sus alteraciones

Peer Reviewe

La ventilación mecánica no invasiva en el paciente pediátrico

La ventilación mecánica en sus dos modalidades, invasiva y no invasiva ha supuesto un avance en el tratamiento de las patologías respiratorias pediátricas tanto crónicas como en el caso de procesos agudos, disminuyendo la morbi-mortalidad asociada a los mismos. Cada modalidad tiene unas indicaciones y/o complicaciones potenciales. Para valorar los distintos sistemas, así como realizar una comparativa de los mismos se llevó a cabo una revisión bibliográfica por medio de PubMed y ScienceDirect mediante el catálogo Almena; los artículos se han buscado tanto en inglés como en castellano, pudiéndose llegar a la conclusión que la ventilación mecánica no invasiva es el tratamiento de primera elección para tratar las bronquiolitis en pacientes pediátricos menores de un año y que entre todos los sistemas la Oxigenoterapia de alto flujo es la que menos complicaciones, mejor tolerancia y menos cargas de trabajo produce.Grado en Enfermerí

Respuesta inmune de las aves y sus alteraciones

Peer Reviewe

Application of Active Flow Control on airfoils at ultralow Reynolds numbers

In a previous research Active Flow Control techniques, such as sweeping jets, applied in an ultra-low Reynolds regime (Re=1000) were found effective to reattach an already separated flow achieving lift enhancements but also inducing a large skin-friction drag increase due to the high velocities near the airfoil surface. In this study, firstly the current actuator configurations have been analyzed with the objective of determining the most important factors involved in the increase of the viscous drag. Then, several hypothesis have been done with the aim of reducing this drag penalty while keeping the lift enhancement. The decision taken in this sense has been to apply geometrical modifications to the the actuators using two control parameters, the jet width and the jet angle in which the fluid is injected. Moreover these modifications have been applied to three different actuation types; blowing, suction and synthetic jets. The simulations have been carried in a 2D NACA0012 airfoil in which a remeshing has been done in order to apply the commented modifications. The obtained results show variations depending on in which actuation type are applied. The jet angle modification has obtained interesting results for the blowing jet, since an angle that maximizes the lift coefficient has been found. The jet width has also obtained an optimum value for a specific momentum coefficient, that moreover is suitable for the three actuations. In conclusion, it has been proved that that besides the momentum coefficient and the jet location the geometrical parameters of the actuator have also a considerable impact on the overall efficiency of the actuation.En un estudio anterior las ténicas de control de flujo activo, como es el caso de los sweeping jets, aplicadas en un Reynolds ultra bajo (Re=1000) demostraron ser efectivas en cuanto al lift se refiere, pero las altas velocidades que provocan cerca de la superficie causaron a su vez un empeoramiento del drag de fricción. En este estudio, se han analizado primero las diferentes configuraciones de actuadores existentes con el objetivo de determinar los factores que más influyen en el aumento del drag viscoso. Después se han propuesto varias hipótesis con el objetivo de reducir el empeoramiento del drag manteniendo el incremento del lift. En este sentido, se ha decidido modificar la geometría de los actuadores usando dos parámetros de control; el ancho del jet y el ángulo en el cual se inyecta el fluido. Estas modificaciones se han aplicado a tres tipos de actuaciones; soplado, succión y synthetic jets. Para las simulaciones se ha usado un perfil NACA00122D, en el cual se ha modificado el mallado para poder incluir los cambios en la geometría.Los resultados obtenidos difieren según el tipo de actuación en el cual son aplicados. La modificación del ángulo del jet ha obtenido resultados interesantes en el caso del soplado, en el cual se ha encontrado un ángulo que maximiza el lift. En el caso del ancho del jet también se ha encontrado un valor óptimo para el coeficiente de momento utilizado, que además es aplicable para los tres tipos de actuaciones. En definitiva, se ha probado que además del coeficiente de momento y la posición del actuador las características geométricas de los actuadores también juegan un papel destacable en la eficiencia de la actuación

Socio-spatial change in the world heritage site Valparaíso

Valparaíso’s old town is one of five world heritage sites in Chile. Its districts of Puerto and Financiero on the coastal platform, together with the surrounding hills of Cerros Concepción and Alegre make up 0.9 % of the total urbanised area. The unique urban ensemble with its heritage of early industrialisation, the harbour installations and the many wooden funiculars have led UNESCO to make these districts a protected area. However, protection does not only mean conservation. Many morphological, functional and socio-spatial changes have taken place since the declaration as a heritage site. Some of them are due to the effects of natural and man-made disasters, but many are a result of the new function as a heritage site. Based on a morphological and functional analysis and a deeper look at the socio-spatial changes, the study returns contradictory results. Initial trends of gentrification can be observed, which may favour the conservation of the built environment, but weaken the social situation. A more severe degradation of the building stock has been halted; however, in many respects dilapidation has only been slowed down. The negative demographic trend has been exacerbated by the activities of ruthless developers who have bought up buildings with speculation in mind. Such activities have a long-term destructive effect on the immaterial cultural heritage, i.e. the vibrant and locally specific urban life in the old town. The main question is how the declaration as a world heritage site has influenced the social and economic fabric of the old town, and how the changes can be evaluated. This paper investigates the socio-economic changes, social transformations and other processes of change