Multipacket reception in LTE femtocell networks

Dissertação apresentada para obtenção do Grau de Mestre em Engenharia Electrotécnica e de ComputadoresDriven by the growing demand for high-speed broadband wireless services, LTE technology has emerged and evolve, promising high data rates to the demanding mobile users. Based on the 3rd Generation Partnership Project (3GPP) speci cations,Long Term Evo- lution Advanced (LTE-A) telecommunication services predict the existence of macro base stations, Enhanced Node B (eNB) and micro stations HeNB with low power that complements the network's coverage. This dissertation studies the complementary use of HeNBs (femtocells 3GPP terminology) to provide broadband services. It is essential to maintain the networks performance with the network densi cation phenomenon, which brings signi cant interference problems and consequently more collisions and lost packets. The use of SC-FDE in the downlink of a LTE-A femtocell network - speci cally multipacket reception (MPR), with an IB-DFE receiver employing Multipacket Detection (MPD) and SIC techniques is proposed. A new telecommunications concept named GC emerged with the increasing environmental concerns. This dissertation shows the performance results of an iterative MPR and proposes a green association algorithm to change the network layout according to the mobile users demands reducing the Base Station (BS)'s negative contribution to the network total energy consumption. The overall results show that the technologies employed are a solution to achieve a favorable trade-o between performance and Energy E ciency (EE), responding to the global demands (high data rates) and concerns (low energy consumption and carbon footprint reduction). Keywords: Long Term Evolution(LTE), Single Carrier with Frequency Domain Equalization (SC-FDE), Iterative Block-Decision Feedback Equalizer (IB-DFE), Home enhanced Node B (HeNB), Successive Interference Cancellation(SIC),Multipacket Reception(MPR), Green Communications (GC)FCT/MEC Femtocells(PTDC/EEATEL/120666/2010), OPPORTUNISTIC CR(PTDC/EEA-TEL/115981/2009) and ADIN(PTDC/EEI-TEL/2990/2012) project

Balancing the arrival times of users in a two-stage location problem

There has been a number of facility location problems dealing with the introduction of the equity issue in the travel distances distribution. In this paper we analyze a new aspect of equity concerning the distribution of the arrival times of customers. Given a depot and a set of demand points generating flow which also represent potential locations, we consider a discrete two-stage location problem whose aim is to locate a given number of facilities and to allocate the demand points to a facility. We assume as objective the maximization of the minimum difference between two consecutive arrival times of flows to the depot through the patronized facility. This particular equity measure is introduced in order to reduce risks of congestion in the dynamic of flow arrivals at the common destination. The problem is described through two Integer Programming formulations. Computational results for solution methods based on both formulations are then shown and analyzed

River restoration and rehabilitation as a new urban design strategy: learning to re-see urban rivers

This study analyses how river restoration-rehabilitation concepts can be transferred from natural settings to constructed environments and thus form part of an urban design strategy. In contrast to conventional civil engineering, this strategy explores how hydraulic challenges can be tackled through instead of against nature. The study focuses on urban rivers in Chile where unstable geographical and environmental conditions in combination with limited budgets require innovative solutions. The methodology uses research by design. From an environmental viewpoint, river restoration know-how is shifted from a restoring tool to a spatial analysis tool focused on understanding natural spatial processes. The outcome of this study is a cartography that maps the dynamic interplay between the natural water system and the city of Concepcion’s environmental conditions on the one hand and the relationship between the river landscape and urban development on the other

Conflicto Reino Unido de Gran Bretaña e Irlanda del Norte y República Argentina

En el estudio del sistema de relaciones de este conflicto, hemos dividido el trabajo en dos partes: 1. Descubrimiento desde 1502 a 1764 y 2. Ocupación desde 1764 a 1954.  Si existen dudas con respecto al descubrimiento de las Islas Malvinas, sin embargo, se admite con absoluta certeza, que los primeros ocupantes y colonizadores del archipiélago fueron los franceses.  Interesa pues dedicarse a este aspecto, ya que él mismo indica una nueva etapa en el sistema de relaciones entre los actores principales del conflicto y antes de la ocupación argentina

Colunas mistas parcialmente revestidas: efeito da resistência e rigidez na resistência à flambagem sob ação do fogo

Colunas mistas, parcialmente revestidas com concreto, apresentam melhor desempenho estrutural que colunas apenas de aço. O concreto entre os banzos do perfil metálico, aumenta a resistência ao fogo da coluna, além da resistência e rigidez, sendo necessário determinar esta propriedade para estes elementos estruturais. O Eurocódigo 4 parte 1-2, no anexo G, apresenta um método simplificado de cálculo para determinar a resistência ao fogo das colunas mistas parcialmente revestidas, calculando a resistência à flambagem, em relação ao eixo de menor momento de segunda ordem, quando expostas a curva de incêndio padrão. Estudos feitos por A. Fellouh e melhorados por L. Calió, determinam que a norma apresenta resultados inseguros, propondo novas equações e parâmetros para o método da soma ponderada presente no anexo G. Neste sentido, o presente trabalho visa propor um novo aprimoramento para o modelo simplificado de cálculo, utilizando novas formulações, provenientes dos resultados de simulações térmicas transientes não lineares, utilizando o programa ANSYS. Foram estudadas trinta configurações de colunas mistas parcialmente revestidas, sendo dez perfis de cada uma das seguintes séries, HEB, HD e UC. Os resultados das simulações numéricas foram usados para realizar o aprimoramento do modelo, sendo este comparado com a sua atual versão do Eurocódigo. Os resultados obtidos com a atual proposta para o modelo, apresentam valores mais seguros, quando comparados com a atual versão do Eurocódigo. Existe uma boa concordância entre os resultados numéricos e o novo modelo de solução proposto.Composite columns, partially encased with concrete, present a better structural performance than bare steel columns. The concrete between the flanges, increases the fire resistance of the column, besides the strength and stiffness, being necessary to determine this property for this type of structural element. The Eurocode 4, in the annex G, presents a simplified calculation method to determine the fire resistance of the partially encased columns, calculating the buckling resistance, around the weak axis, when exposed to the standard fire curve. Studies developed by A. Fellouh and improved by L. Calió, concluded for unsafe results when using the Eurocode, proposing new equations and parameters for the balanced summation model presented in the annex G. This study aims to propose a new improvement for the simplified calculation model, using new formulae, based on thermal transient nonlinear simulation result, developed with the software ANSYS. This investigation deals with thirty different cross sections of partially encased columns, being ten of each specified for the profile series, HEB, HD and UC. The numerical simulation results were used to improve the model, being this solution compared with the current version of Eurocode. The results obtained with the current proposal model present safer values when compared with the current version of Eurocode. There is a good agreement between the numerical results and the new proposed solution model

Malvinas en la Agenda de Política Exterior Argentina.

En españolEl autor analiza como la Adminsitración Menem significó un cambio profundo en la Política Exterior Argentina en relación a Malvinas. Destaca de que manera se privilegia la relación bilateral en lugar del marco multilateral, y como el canciller Di Tella decide tener en cuenta los deseos de los habitantes de las Islas rompiendo con una tradición histórica mantenida por Argentina en Naciones Unidas desde 1965 También se demuestra la contradicción entre el discurso y la realidad, a través de los mensajes que el Presidente Menem dirigió a la Asamblea Legislativa durante los últimos años sobre los derechos argentinos sobre las Islas y la prioridad que el mismo gobierno le otorga a los temas bilaterales económicos o comerciales, en su relación con el reino Unido, comprometiendo la suerte de la soberanía sore Malvinas.En inglésThe author analyses how Menem Administration has meant a deep change as regards Argentinian Foreing policy on Malvinas. He points out how the bilateral relation is privileged over the multilateral frame, as well as how Foreing Minister Di Tella has decided to take into consideration the desires of the islands' in habitants. By doing this, he has broken a whole historic tradition, kept by Argentina in the United Nations since 1965. Professor Bologna also shows the contradiction between discuorse and reality, through the messages President Menem adressed to the Legislative Assembly over the last few years, on the one hand; while, on the other, the government assigns priority, to the economic and commercial bilateral issues in their relationship with the United Kingdom. In this way, sovereignty is put at the ris

LA DEMOCRACIA Y LA ORGANIZACION DE ESTADOS AMERICANOS.

En españolEl trabajo tiene como objetivo analizar el comportamiento de la Organización de Estados Americanos (OEA) frente a los Golpes de Estado que se produjeron en la región Latinoamericana a partir de la década del 90. A partir de la XXI Asamblea General de la OEA realizada en Santiago de Chile en Junio de 1991, se establece un compromiso para el fortalecimiento democrático y se aprueba una resolución por la cual se debe convocar a una reunión de cancilleres en caso de un Golpe de Estado y la OEA podrá tomar las medidas que crea conveniente para restablecer la institucionalidad democrática. Se pretende observar el accionar de la OEA frente a los Golpes de Estado en Haití, Venezuela (fracazado) y Perú y la posible aplicación futura del artículo 8 bis de la Carta por el cual se debe suspender de la Organización al país en el cual se produce un Golpe de Estado.En inglésThe aim of this paper is to analyse the OAS (Organization of American States) reaction to the military coups in Latin America during the nineties. On ocassion of the XXI OAS General Assembly held in Santiago de Chile in June, 1991, a compromise was reached to promete the strengthening of democracy. A resolution was approved, which established that, in case of a military coup, a meeting of Foreign Ministers should be called, and the OAS should be able to take all the necessary steps to restore democracy. The OAS role in the case of the violent interruption of democratie regimes in Haití, Venezuela (which failed), and Perú, will be studied, as well as the possible application of article 8 bis of the Charter, which set up that in such a cases the state's member ship to the OAS should be suspended