[pt] Este trabalho tem como foco o up-grade da taxa de bits em enlaces ópticos através da tecnologia OTDM. Os sistemas analisados contemplam os up-grades das taxas de 2,48 Gbps para 10 Gbps e também da taxa de 10 Gbps para 40 Gbps. Para tal, foram introduzidos módulos de transmissão e recepção, capazes de utilizar arquiteturas quase totalmente ópticas. É avaliado então, através de simulações, o comportamento da arquitetura proposta em infra-estruturas de enlaces já instalados no Brasil, destacando os pontos mais críticos. No que se refere ao up-grade de 10 Gbps para 40 Gbps, foi dado enfoque especial para as penalidades relativas à PMD (Polarization Mode Dispersion). / [en] This work aims at up grading the bit rate of optical links through the OTDM technology. The analyzed up-grades change the bit rate of 2,48 Gbps up to 10 Gbps and also from the bit rate of 10 Gbps up to 40 Gbps. To reach these objectives, transmission and reception modules were introduced, using all optical networks topologies. The performance of the proposed architecture was simulated using a infrastructure of links already installed in Brazil. The most critical issues were pointed out. Concerning the up-grade from 10 Gbps to 40 Gbps, a special focus was given to the penalties due to PMD (Polarization Mode Dispersion).

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The relationship between international investment agreements and EU law has attracted increased attention in past few years. The aim of this thesis is to bring a detailed analysis of various aspects of this complicated relationship. In attainment of this aim it proceeds in the following steps. After a short introduction (Chapter I.), Chapter II. briefly overviews typical content of bilateral investment treaties, following with a more detailed analysis of relevant EU law rules concerning foreign investment and subsequent comparison of both sets of rules. Chapter III. deals with investment agreements to be concluded by the EU, in particular with questions of external competence for foreign investment, responsibility for breaches of investment agreements concluded by the EU and the future shape of EU investment policy. The status of existing bilateral investment treaties concluded between EU member states and third countries is analyzed in Chapter IV. Chapter V. tackles various issues related to investment treaties concluded between member states (so called intra-EU BITs).

Investment Policy of the European Union - protection of foreign direct investment Abstract One of the changes brought about by the Lisbon Treaty is the explicit inclusion of foreign direct investment and its protection in the common commercial policy of the European Union. This is one of the areas of exclusive competence of the EU. The European Union has subsequently stated negotiating bilateral agreements governing, inter alia, investment issues. However, it has not been spared from controversy and negative publicity that has been accompanying especially the TTIP and the CETA. This work aims to analyse the investment policy of the EU and mutual interaction of its institutions with the Member States and third parties. After general introduction to the topic of international investment law and EU law (chapters II. and III.), it is devoted to the issue of protection of foreign investment in the internal market. Its regime is then compared with the BIT regime (chapter IV.). Attention is then focussed towards the EU's external relations in the field of investment protection. Its competence is subjected to further analysis (chapter V.) and current results of efforts of the Commission and the EU as such are also discussed (chapter VI.). It is so in the light of possible impacts of foreign investment in terms of...

Dans une première partie, nous définissons plusieurs schémas de compression en partant de l'état de l'art qu'est JPEG 2000 aujourd'hui. Les schémas de compressions que nous avons définis proposent d'utiliser une transformation pour la réduction de la redondance spatiale transformée en ondelette discrète (TOD) et une autre transformation pour réduire la redondance spectrale. Les transformations optimales sous les hypothèses faible distortion, permettant de réduire la redondance spectrale, s'obtiennent dans certains cas en minimisant un critère qui peut être interprété comme le critère de l'analyse en composantes indépendantes (ACI) (minimisation de l'information mutuelle) additionné d'un terme toujours positif ou nul qui est une certaine mesure à l'orthogonalité de la transformation obtenue. Les performances obtenues en intégrant ces transformations dans nos schémas de compression montrent une amélioration des performances en comparaison à la transformation de Karhunen Loève (TKL). Dans la deuxième partie, nous proposons un modèle de mélange convolutif pour rechercher une transformation unique réduisant à la fois les redondances spatiales et spectrales. Nous définissons le critère à minimiser sous les hypothèses faibles distortions et nous montrons que ce critère peut s'interprété comme celui de l'ACI pour la séparation et déconvolution lorsque le critère à minimiser est l'information mutuelle auquel s'additionne un terme toujours positif ou nul. Puis nous proposons deux algorithmes permettant d'obtenir d'une part la transformation minimisant le critère dans le cas général, et d'autre part celle qui minimise le critère sous la contrainte que la distorsion dans le domaine transformée est la même que celle du domaine de l'image.

Submitted by Fernando Mistura (f.mistura@gmail.com) on 2011-10-10T19:43:49Z No. of bitstreams: 1 20111010 - ThesisMistura.pdf: 9859237 bytes, checksum: 549c3f8971cac6c47966b93ec2c8debc (MD5) / Approved for entry into archive by Gisele Isaura Hannickel (gisele.hannickel@fgv.br) on 2011-10-10T19:48:44Z (GMT) No. of bitstreams: 1 20111010 - ThesisMistura.pdf: 9859237 bytes, checksum: 549c3f8971cac6c47966b93ec2c8debc (MD5) / Approved for entry into archive by Gisele Isaura Hannickel (gisele.hannickel@fgv.br) on 2011-10-10T19:48:59Z (GMT) No. of bitstreams: 1 20111010 - ThesisMistura.pdf: 9859237 bytes, checksum: 549c3f8971cac6c47966b93ec2c8debc (MD5) / Made available in DSpace on 2011-10-11T12:42:21Z (GMT). No. of bitstreams: 1 20111010 - ThesisMistura.pdf: 9859237 bytes, checksum: 549c3f8971cac6c47966b93ec2c8debc (MD5) Previous issue date: 2011-10-07 / This dissertation has sought to identify the role of BRIC country governments in the internationalization of their firms. Drawing upon an exploratory comparative analysis of BRIC OFDI trends and policies, it contributes to further an initial understanding of this phenomenon by shedding light on how and why BRIC governments have been promoting their multinationals. For this, it analysed specific OFDI-related policies implemented by BRIC countries as a way of highlighting policy-gaps and the effects of institutional set-ups in the development of internationalized companies. The rapid rise of MNCs from BRIC countries is quite a recent phenomenon. Although they had invested abroad before, only since the early 2000s OFDI by BRIC MNCs has become substantial. BRIC MNCs are becoming major players in many industries, taking-over competitors in both developed and developing countries, and reshaping competition in many industries. In this process, BRIC governments have played an important role. While until the early 1990s, BRIC governments restricted OFDI because of a negative perspective on its effects on home economies (e.g., reduction in investments at home, exports of jobs, and constraints to the balance-of-payments), in the 2000s their perception of OFDI changed. They have become more aware of the importance of OFDI for the competitiveness of their firms and industrial upgrade. While China, and to a lesser extent India, are one step further, having already put in place a comprehensive set of specific OFDI promoting policies, Brazil and Russia have yet to take further steps in order to create an enabling environment for their companies to fully exploit the advantages of global expansion / Esta dissertação procurou identificar o papel dos governos na internacionalização produtiva de empresas dos países BRIC. Por meio de uma análise comparativa do comportamento dos investimentos diretos no exterior (IDE) destes países e dos mecanismos existentes de suporte à internacionalização das empresas, foi possível identificar as diferentes maneiras de envolvimento desses governos na internacionalização produtiva de suas empresas e apontar lacunas de políticas públicas nestes países. Destarte, esta dissertação contribui à compreensão inicial sobre como e por que os governos destes países têm promovido o desenvolvimento de multinacionais. A rápida ascensão das multinacionais dos países BRIC é um fenômeno recente. Apesar de terem investido no exterior anteriormente, apenas a partir do início dos anos 2000 que o IDE de empresas destes países tornou-se significativo. Desde então, as multinacionais dos países BRIC estão se tornando importantes players em diversas indústrias, adquirindo competidores de países desenvolvidos e em desenvolvimento, e redesenhando a concorrência em muitas indústrias globais. Neste processo, os governos dos países BRIC têm desempenhado um papel importante. Até o início dos anos 1990, o IDE era restringido porque era associado a efeitos negativos sobre as economias domésticas (como por exemplo, à redução de investimentos no país de origem, à exportação de empregos, e a problemas na balança de pagamentos). Desde o início dos anos 2000, entretanto, os governos dos países BRIC mudaram de percepção e passaram a adotar políticas favoráveis à internacionalização produtiva de empresas domésticas. Eles perceberam a importância da internacionalização para a manutenção ou expansão da competitividade das empresas domésticas em um mundo globalizado. A China, e em menor grau a Índia, estão um passo adiante, tendo já posto em prática um conjunto de instrumentos específicos que facilitam a internacionalização de suas empresas. O Brasil e a Rússia ainda têm de tomar novas medidas para criar um ambiente propício para que suas empresas possam mais facilmente explorar as vantagens da expansão global.

[pt] Esta dissertação propõe algoritmos para codificações de voz a taxas médias em torno de 1,2 Kb/s. Um esquema de quantização vetorial preditiva chaveada com desempenho superior aos esquemas previamente descritos na literatura é proposto e avaliado em canal com ou sem ruído. Detectores eficientes de período fundamental e de sons oclusivos e fricativos são examinados e adaptados ao codificador proposto. Técnicas de exitação a baixas taxas de bits são investigadas a fim de reproduzir uma boa qualidade de voz decodificada. O modelo de exitação mista em multi-bandas com três sub-bandas é adotado para codificar os quadros sonoros. Para os quadros surdos são empregadas técnicas de modelagem e síntese de sinais fricativos e oclusivos, capazes de oferecer qualidade de voz satisfatória, reduzindo a taxa de bits destes quadros para apenas 0,4 Kb/s. Técnicas de pós-filtragem para reduzir o ruído de codificação e melhorar a qualidade de voz reconstruída são também examinadas e comparadas em uma mesma plataforma. Para reduzir o nível de ruído ambiente são ainda analisados métodos de supressão de ruído. Finalmente, o codificador proposto é comparado ao padrão norte-americano Mixed Excitation Linear Prediction (MELP), por meios de teste de comparação do tipo A/B. Os testes realizados indicam que o sistema proposto, operando a 1,2 Kb/s, apresenta qualidade de voz ligeiramente superior ao MELP, operando a 2,4 Kb/s. Para situações de transcodificação, o codificador proposto também apresenta desempenho superior ao MELP. / [en] This dissertation presents algorithms to encode at an avarage bit rate of 1.2 Kb/s. A novel switched-predictive vector quantiser technique that outperforms previously reported schemes is proposed and assessed under noise-free and noisy channels. Efficient detectors for the pitch period and fricative and stop sounds are examined and adapted to the proposed coder. Low bit rate excitation methods are investigated in order to reproduce rather high quality speech. A mixed multiband excitation approach with three sub-bands is employed to encode voiced frames. For unvoiced frames, fricatives and stops modelling and synthesis techniques are used. This approach has shown to provide high quality synthesised speech, whilts it reduces the bit rate to only 0.4 Kb/s for unvoiced frames. To reduce coding noise and improve decoded speech, post- filtering techniques are analysed and compared on the same plataform. To reduce background noise, noise suppression methods are also examined. Finally, the propose coder is evaluated against the North American Mixed Prediction (MELP) coder, through A/B comparison tests. Assessment results have shown that the proposed system, operating at 1.2 Kb/s, slightly outperformed the MELP coder, operating at 2.4 Kb/s. For tandem connection situations, the proposed algorithm has presented a superior performance than the MELP coder. / [es] Esta disertación propone algoritmos para codificaciones de voz a tasas medias en torno de 1,2 Kb/s. Se propone un esquema de cuantización vectorial predictiva, con desempeño superior a los esquemas previamente descritos en la literatura. Este esquema se evalúa en canal con o sin ruido. Se examinan detectores eficientes de período fundamental y de sueños oclusivos y fricativos se adaptan al codificador propuesto. Técnicas de exitación a bajas tasas de bits son investigadas a fin de reproducir una boa calidad de voz decodificada. Se adopta el modelo de exitación mixta en multi-bandas con tres sub-bandas para codificar los cuadros sonoros. Para los cuadros surdos se emplean técnicas de modelación y síntesis de señales fricativos y oclusivos, capaces de ofrecer calidad de voz satisfactoria, reduciendo la tasa de bits de estos cuadros para apenas 0,4 Kb/s. También se examinan y se comparan las técnicas de pós-filtragen para reducir el ruido de codificación y mejorar la calidad de voz reconstruída. Para reducir el nível de ruído ambiente se analizan métodos de supresión de ruido. Finalmente, el codificador propuesto se compara al padrón norteamericano Mixed Excitation Lineal Prediction (MELP), por medio de pruebas de comparación del tipo LA/B. Las pruebas realizadas indican que el sistema propuesto, operando a 1,2 Kb/s, presenta calidad de voz ligeramente superior al MELP, operando a 2,4 Kb/s. Para situaciones de transcodificación, el codificador propuesto también presenta desempeño superior al MELP.

To meet the exponentially increasing traffic data driven by the rapidly growing mobile subscriptions, both industry and academia are exploring the potential of a new genera- tion (5G) of wireless technologies. An important 5G goal is to achieve high data rate. Small cells with spectrum sharing and multiple-input multiple-output (MIMO) techniques are one of the most promising 5G technologies, since it enables to increase the aggregate data rate by improving the spectral efficiency, nodes density and transmission bandwidth, respectively. However, the increased interference in the densified networks will in return limit the achievable rate performance if not properly managed. The considered setup can be modeled as MIMO interference networks, which can be classified into the K-user MIMO interference channel (IC) and the K-cell MIMO interfering broadcast channel/multiple access channel (MIMO-IBC/IMAC) according to the number of mobile stations (MSs) simultaneously served by each base station (BS). The thesis considers two physical layer (PHY) resource allocation problems that deal with the interference for both models: 1) Pareto boundary computation for the achiev- able rate region in a K-user single-stream MIMO IC and 2) grouping-based interference alignment (GIA) with optimized IA-Cell assignment in a MIMO-IMAC under limited feedback. In each problem, the thesis seeks to provide a deeper understanding of the system and novel mathematical results, along with supporting numerical examples. Some of the main contributions can be summarized as follows. It is an open problem to compute the Pareto boundary of the achievable rate region for a K-user single-stream MIMO IC. The K-user single-stream MIMO IC models multiple transmitter-receiver pairs which operate over the same spectrum simultaneously. Each transmitter and each receiver is equipped with multiple antennas, and a single desired data stream is communicated in each transmitter-receiver link. The individual achievable rates of the K users form a K-dimensional achievable rate region. To find efficient operating points in the achievable rate region, the Pareto boundary computation problem, which can be formulated as a multi-objective optimization problem, needs to be solved. The thesis transforms the multi-objective optimization problem to two single-objective optimization problems–single constraint rate maximization problem and alternating rate profile optimization problem, based on the formulations of the ε-constraint optimization and the weighted Chebyshev optimization, respectively. The thesis proposes two alternating optimization algorithms to solve both single-objective optimization problems. The convergence of both algorithms is guaranteed. Also, a heuristic initialization scheme is provided for each algorithm to achieve a high-quality solution. By varying the weights in each single-objective optimization problem, numerical results show that both algorithms provide an inner bound very close to the Pareto boundary. Furthermore, the thesis also computes some key points exactly on the Pareto boundary in closed-form. A framework for interference alignment (IA) under limited feedback is proposed for a MIMO-IMAC. The MIMO-IMAC well matches the uplink scenario in cellular system, where multiple cells share their spectrum and operate simultaneously. In each cell, a BS receives the desired signals from multiple MSs within its own cell and each BS and each MS is equipped with multi-antenna. By allowing the inter-cell coordination, the thesis develops a distributed IA framework under limited feedback from three aspects: the GIA, the IA-Cell assignment and dynamic feedback bit allocation (DBA), respec- tively. Firstly, the thesis provides a complete study along with some new improvements of the GIA, which enables to compute the exact IA precoders in closed-form, based on local channel state information at the receiver (CSIR). Secondly, the concept of IA-Cell assignment is introduced and its effect on the achievable rate and degrees of freedom (DoF) performance is analyzed. Two distributed matching approaches and one centralized assignment approach are proposed to find a good IA-Cell assignment in three scenrios with different backhaul overhead. Thirdly, under limited feedback, the thesis derives an upper bound of the residual interference to noise ratio (RINR), formulates and solves a corresponding DBA problem. Finally, numerical results show that the proposed GIA with optimized IA-Cell assignment and the DBA greatly outperforms the traditional GIA algorithm.

The aim of this work was to peruse and desribe the high-speed data technology communicating over energy network. In this work was investigated broadband system communicating over low power distribution network. The laboratory network was designed for measuring parametres of this communication and performed set of tests. Lended devices were described, properties of technology specification and methods of connection and management were introduced. Management, configuration and measuring over web interface on the NMS device was described and simple dividision into corresponding functional blocks corresponding to structure of web bookmaks was made. Metodology of individual tests, grounded on documentation “recomandation” RFC and on introduced works, was elaboratly described. Used tools, their properties and managements were described. The transmission speed on application and physical layer were followed primarily, frequency dependencies on signal noise ratio and bits per carrier were followed secondary. Measured results from individuals tests were compared among each other and evaulated. This observation leaded into decision on needed criteria for varius application. The suitaibility for integration into communication network for maintaining corresponding QoS was appreised. Testing and chosen types of tests in this project were standardized and integrated into ITU standard. Individual tests are able to compare from the view of their testify charactestic.