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The explosion in mobile data traffic is a driver for future network operator technologies, given its large potential to affect both network performance and generated revenue. The concept of distributed mobility management (DMM) has emerged in order to overcome efficiency-wise limitations in centralized mobility approaches, proposing not only the distribution of anchoring functions but also dynamic mobility activation sensitive to the applications needs. Nevertheless, there is not an acceptable solution for IP multicast in DMM environments, as the first proposals based on MLD Proxy are prone to tunnel replication problem or service disruption. We propose the application of PIM-SM in mobility entities as an alternative solution for multicast support in DMM, and introduce an architecture enabling mobile multicast listeners support over distributed anchoring frameworks in a network-efficient way. The architecture aims at providing operators with flexible options to provide multicast mobility, supporting three modes: the first one introduces basic IP multicast support in DMM; the second improves subscription time through extensions to the mobility protocol, obliterating the dependence on MLD protocol; and the third enables fast listener mobility by avoiding potentially slow multicast tree convergence latency in larger infrastructures, by benefiting from mobility tunnels. The different modes were evaluated by mathematical analysis regarding disruption time and packet loss during handoff against several parameters, total and tunneling packet delivery cost, and regarding packet and signaling overhead.

[EN] This paper deals with the thermodynamic analysis of an absorption refrigeration cycle used to cool down the temperature of the intake air in an Internal Combustion Engine using as a heat source the exhaust gas of the engine. The solution of ammonia-water has been selected due to the stability for a wide range of operating temperatures and pressures and the low freezing point. The effects of operating temperatures, pressures, concentrations of strong and weak solutions in the absorption refrigeration cycle were examined to achieve proper heat rejection to the ambient. Potential of increasing Internal Combustion Engine efficiency and reduce pollutant emissions was estimated by means of theoretical models and experimental tests. In order to provide boundary conditions for the absorption refrigeration cycle and to simulate its effect on engine performance, a OD thermodynamic model was used to reproduce the engine performance when the intake air is cooled. Furthermore, a detailed experimental work was carried out to validate the results in real engine operation. Theoretical results show how the absorption refrigeration system decreases the intake air flow temperature down to a temperature around 5 degrees C and even lower by using the bottoming waste heat energy available in the exhaust gases in a wide range of engine operating conditions. In addition, the theoretical analysis estimates the potential of the strategy for increasing the engine indicated efficiency in levels up to 4% also at the operating conditions under evaluation. Finally, this predicted benefit in engine indicated efficiency has been experimentally confirmed by direct testing. (C) 2016 Elsevier Ltd. All rights reserved., Authors want to acknowledge the "Apoyo para la investigacion y Desarrollo (PAID)" grant for doctoral studies (FPI S2 2015 1067).

De acuerdo a los objetivos específicos, el trabajo se estructuró en tres capítulos, en el primero, se fundamenta el marco conceptual y de antecedentes para comprender el caso de la Asamblea Popular Constituyente como un ejercicio de gobernabilidad democrática, en el segundo capítulo, se describe el surgimiento y consolidación de la Asamblea Popular Constituyente en el Municipio de Morales y las características de la misma; en el último capítulo, se analizan los desafíos de la acción colectiva en contextos de conflicto armado y abandono estatal frente a la construcción de cultura democrática y gobernabilidad territorial en Colombia. According to the specific objectives, the work was structured in three chapters, in the first, the conceptual and background framework is based to understand the case of the Popular Constituent Assembly as an exercise of democratic governance, in the second chapter, it is described the emergence and consolidation of the Popular Constituent Assembly in the Municipality of Morales and its characteristics; In the last chapter, the challenges of collective action in contexts of armed conflict and state abandonment are analyzed in the face of the construction of a democratic culture and territorial governance in Colombia. Introducción ……………………………………………………………………………………………………………………………………..9 Capítulo 1 …………………………………………………………………………………………………………….…………………………..16 1. Gobernabilidad Democrática, Conflicto Armado y Resistencia Civil……………………………………………….16 1.1. De la gobernabilidad democrática a la gobernabilidad territorial……………………………………………….16 1.1.1 La gobernanza………………………………………………………………………………………………………………………….22 1.1.2 Gobernabilidad y gobernanza, el caso colombiano…………………………………………………………………..26 1.2 conflicto interno y dinámicas de territoriales………………………………………………………………………………28 1.3 Resistencia civil y cultura democrática…………………………………………………………………………………………22 Capítulo 2………………………………………………………………………………………………………………………………………….38 2. El proceso de la Asamblea popular constituyente de Micoahumado…………………………………………….38 2.1 El Magdalena medio como espacio de conflicto territorial…………………………………………………………..38 2.1.1 El sur de Bolívar en el magdalena medio…………………………………………………………………………………..42 2.2 El municipio de Morales en el escenario del conflicto armado en Colombia………………………………..56 2.2.1 Localización y aspectos generales……………………………………………………………………………………………..57 2.2.2 Potencialidades del territorio……………………………………………………………………………………………………60 2.2.3 Situación sociopolítica: riquezas y riesgos…………………………………………………………………………………61 2.3 La Asamblea popular constituyente de Micoahumado………………………………………………………………..64 2.3.1Surgimiento y consolidación de la Asamblea popular constituyente de Micoahumado como experiencia de resistencia civil noviolenta…………………………………………………………………………………………64 2.3.2 El proceso organizativo de la asamblea popular constituyente de Micoahumado…………………….70 2.3.3 La asamblea popular constituyente de Micoahumado como experiencia de resistencia civil frente al conflicto armado: mediación con diferentes actores y escenarios………………………………………………….73 Capítulo 3……………………………………………………………………………………………………………………………….…………78 3. Desafíos para construcción de cultura democrática y gobernabilidad territorial en contextos de conflicto armado y abandono estatal………………………………………………………………………………………………..78 3.1. La soberanía popular y cultura democrática……………………………………………………………………………….83 3.2 La relación Estado-Ciudadanía en la gobernabilidad territorial……………………………………………………85 3.3 Los desafíos de la Asamblea popular constituyente: retos para la paz………………………………………….84 Conclusiones…………………………………………………………………………………………………………………………………….88 Bibliografía……………………………………………………………………………………………………………………………………….92 Anexos………………………………………………………………………………………………………………………………………………96 Maestría

The depth of focus (DOF) defines the axial range of high lateral resolution in the image space for object position. Optical devices with a traditional lens system typically have a limited DOF. However, there are applications such as in ophthalmology, which require a large DOF in comparison to a traditional optical system, this is commonly known as extended DOF (EDOF). In this paper we explore Programmable Diffractive Optical Elements (PDOEs), with EDOF, as an alternative solution to visual impairments, especially presbyopia. These DOEs were written onto a reflective liquid cystal on silicon (LCoS) spatial light modulator (SLM). Several designs of the elements are analyzed: the Forward Logarithmic Axicon (FLAX), the Axilens (AXL), the Light sword Optical Element (LSOE), the Peacock Eye Optical Element (PE) and Double Peacock Eye Optical Element (DPE). These elements focus an incident plane wave into a segment of the optical axis. The performances of the PDOEs are compared with those of multifocal lenses. In all cases, we obtained the point spread function and the image of an extended object. The results are presented and discussed. © 2015 SPIE. Federación Española de Enfermedades Raras, FEDER Pontificia Universidad Javeriana;Universidad Antonio Narino;Universidad de Cartagena;Universidad Nacional de Colombia

This paper deals with shielding resonator structures for possible application in electromagnetic rail launchers. The main aspects of the resonant shield are revisited via the “spatial averaging” concept of macroscopic quantities and of the effective magnetic behavior. In particular, it is recalled how a resonator structure defines a spatial region with effective negative permeability and it is shown how this can be exploited for shielding applications. Simulation results are obtained via a commercial finite element code through a three dimensional frequency analysis. The shielding effectiveness is estimated at different operating conditions by varying the resonance frequencies of the shield, while maintaining constant the field operating frequency. Possible advantages and critical aspects of such an approach are discussed throughout the paper, and a preliminary analysis of the thrust force acting on the projectile is also provided.