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This project deliverable summarizes the technical discussions and presents the slides and additional decisions and technical information concerning the SFI2 Project Workshop realized in Uberlândia, Minas Gerais. The SFI2 project (https://sites.google.com/view/sfi2/home) workshop presentations and technical discussions occurred at the Federal University of Uberlândia (UFU) on April 12th - 13th 2023., {"references":["G. N. Dias, J. F. Rezende, L N. Ciuffo, I. Machado, Flavio Silva, Tereza C. de Brito, F. Redigolo, Joberto S. B. Martins, Leobino Sampaio, and Antonio Abelem. SFI2 - Slicing Future Internet Infrastructures project. In Proceedings of the The Global Experimentation for Future Internet, pages 1–3, Coimbra, Portugal, November 2019.","Joberto S B Martins, Tereza C. Carvalho, Flavio Silva, and Rodrigo Moreira. SFI2 Network Slicing Reference Architecture. Technical Report TR03/2022, Universidade de São Paulo - USP, 2022.","Rodrigo Moreira, Joberto S. B. Martins, Tereza C. M. B. Carvalho, and Flávio de Oliveira Silva. On Enhancing Network Slicing Life-Cycle Through an AI-Native Orchestration Architecture. In Leonard Barolli, editor, Advanced Information Networking and Applications, Lecture Notes in Networks and Systems, pages 124–136, Cham, 2023. Springer International Publishing.","Joberto S B Martins. Communication Slice Allocation for Network Slicing - Position Points, volume 24 of JSMNet Networking and Technical Review. 2023."]}

Network Slicing (NS) is an essential technique extensively used in 5G networks computing strategies, mobile edge computing, mobile cloud computing, and verticals like the Internet of Vehicles and industrial IoT, among others. NS is foreseen as one of the leading enablers for 6G futuristic and highly demanding applications since it allows the optimization and customization of scarce and disputed resources among dynamic, demanding clients with highly distinct application requirements. Various standardization organizations, like 3GPP's proposal for new generation networks and state-of-the-art 5G/6G research projects, are proposing new NS architectures. However, new NS architectures have to deal with an extensive range of requirements that inherently result in having NS architecture proposals typically fulfilling the needs of specific sets of domains with commonalities. The Slicing Future Internet Infrastructures (SFI2) architecture proposal explores the gap resulting from the diversity of NS architectures target domains by proposing a new NS reference architecture with a defined focus on integrating experimental networks and enhancing the NS architecture with Machine Learning (ML) native optimizations, energy-efficient slicing, and slicing-tailored security functionalities. The SFI2 architectural main contribution includes the utilization of the slice-as-a-service paradigm for end-to-end orchestration of resources across multi-domains and multi-technology experimental networks. In addition, the SFI2 reference architecture instantiations will enhance the multi-domain and multi-technology integrated experimental network deployment with native ML optimization, energy-efficient aware slicing, and slicing-tailored security functionalities for the practical domain., Comment: 10 pages, 11 figures

The future Internet and computer networks scenario requires a dynamic, on-demand, easily manageable, intelligent, and flexible network capable of supporting the different requirements of current and future applications. For attaining this objective, the research community is turning to the networks of the future involving initiatives such as the Next Generation Internet (NGI) in Europe and Tomorrow’s Internet Project in the United States, in addition to several other actions such as the next generation of mobile telecommunications networks for 2030, 6G. In Brazil, projects such as FIBRE [1], FIWARE [2], FUTEBOL [3], 5GINFIRE[2], NECOS [4], CloudNEXT, and SFI2 [5] [6], carried out in collaborations between Europe and Brazil, create conditions to experiment with different scenarios of networks and applications with a focus on the future. This SFI2 Workshop aims to discuss, exchange research ideas and propose directions and solutions toward the utilization of network slicing (NS) as a new paradigm capable to support future Internet evolution. SFI2 will focus on experimental network integration as a guidance direction for these discussions and proposals., {"references":["Antonio Abelem, Michael Stanton, Iara Machado, Marcos Salvador, Luiz Magalhaes, Natalia Fernandes, Sand Correa, Kleber Cardoso, Cesar Marcondes, Joberto Martins, Jose Monteiro, Tereza Carvalho, and José Rezende. FIT@ BR - A Future Internet Testbed in Brazil. In Proceedings of the APAN – Network Research Workshop, pages 1–8, 2013.","Aloizio P. Silva, Christos Tranoris, Spyros Denazis, Susana Sargento, João Pereira, Miguel Luís, Rodrigo Moreira, Flávio Silva, Ivan Vidal, Borja Nogales, Reza Nejabati, and Dimitra Simeonidou. 5GInfire: An End-to-End Open5G Vertical Network Function Ecosystem. Ad Hoc Networks, 93:101895, October 2019.","Cristiano Both, Rafael Guimaraes, Frank Slyne, Juliano Wickboldt, Magnos Martinello, Cristina Dominicini, Rafael Martins, Yi Zhang, Diego Cardoso, Rodolfo Villaca, Isabella Ceravolo, Reza Nejabati, Johann Marquez-Barja, Marco Ruffini, and Luiz DaSilva. FUTEBOL Control Framework: Enabling Experimentation in Convergent Optical, Wireless, and Cloud Infrastructures. IEEE Communications Magazine, 57(10):56–62, October 2019.","Stuart Clayman, Augusto Neto, Fábio Verdi, Sand Correa, Silvio Sampaio, Ilias Sakelariou, Lefteris Mamatas, Rafael Pasquini, Kleber Cardoso, Francesco Tusa, Christian Rothenberg, and Joan Serrat. The NECOS Approach to End-to-End Cloud-Network Slicing as a Service. IEEE Communications Magazine, 59(3):91–97, March 2021. Conference Name: IEEE Communications Magazine.","Gustavo Neves Dias, José Ferreira Rezende, Leandro Neumann Ciuffo, Iara Machado, Flavio de Oliveira Silva, Tereza Cristina de Brito, Fernando Frota Redigolo, Joberto S. B. Martins, Leobino N. Sampaio, and Antonio Jorge Gomes Abelem. SFI2 - Slicing Future Internet Infrastructures project. In Proceedings of the The Global Experimentation for Future Internet (GEFI), pages 1–3, Coimbra, Portugal, November 2019.","Flávio de Oliveira Silva, Tereza Cristina Carvalho, Joberto S. B. Martins, Cristiano Bonato Both, and Daniel Fernandes Macedo. Slicing Future Internet Infrastructures Round Table. Technical Report TR01/2021, Universidade de São Paulo (USP), São Paulo, Brazil, 2021."]}

Orientador: Dietrich Wilhelm Schleicher Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica, Instituto de Geociências Resumo: A inversão de onda completa (FWI, do inglês ''full waveform inversion'') nãolinear baseada em gradientes (métodos de descida) é, a princípio, capaz de levar em conta todos os aspectos da propagação de onda contida nos dados síismicos. Porém, FWI baseada em gradientes é limitada pela sua bem conhecida sensibilidade no que diz respeito à escolha do modelo inicial. Com o intuito de melhor entender algumas questões relacionadas à convergência do modelo na FWI, nós estudamos uma decomposição baseada na teoria de espalhamento que permite dividir os núcleos de sensibilidade dos campos de onda acústica em função dos parâmetros do modelo em duas partes: uma relativa ao componente de fundo, outra relativa à componente singular do modelo. Estimativas para a perturbação de fundo, bem como para a perturbação da parte singular do modelo obtidas com os adjuntos destes subnúcleos são componentes da estimativa obtida com o adjunto do núcleo total de sensibilidade. Os experimentos numéricos suportam a tese de que a decomposiçao em subnúcleos permite que se retroprojete somente os resíduos do campo de onda espalhado de modo a obter estimativas razoáveis da perturbação de fundo do modelo. Em um experimento com geometria de aquisição restrita (dados de reflexão com afastamento curto), os subnúcleos baseados em espalhamento múltiplo se aproveitam da autoiluminacão do meio devido às ondas multiplamente espalhadas. A autoiluminação fornece estimativas melhores com conteúdo espectral mais rico nas baixas frequências Abstract: While in principle nonlinear gradient-based full-waveform inversion (FWI) is capable of handling all aspects of wave propagation contained in the data, including full nonlinearity, in practice, it is limited due to its notorious sensitivity to the choice of the starting model. To help addressing model-convergence issues in FWI, we study a decomposition based on the scattering theory that allows to break the acoustic-wavefield sensitivity kernels with respect to model parameters into background and singular parts. The estimates for both background perturbation and/or singular-part perturbation obtained with the subkernels' adjoints are components of the estimate obtained with the total kernel's adjoint. Our numerical experiments shows the feasibility of our main claim: the decomposition into subkernels allows to backproject the scattered-wavefield residuals only so as to obtain reasonable background-model perturbation estimates. In an experiment with restricted acquisition geometry (reflection data, narrow offset), the multiple-scattering subkernels take advantage of medium self-illumination provided by the scattered wavefields. This self-illumination provides better estimates, with longer wavelengh content Doutorado Reservatórios e Gestão Doutor em Ciências e Engenharia de Petróleo

Hydrogen (H2) as fuel has been considered as the most promising source of renewable energy to meet growing global demand. Among H2 production methods, water splitting can produce high purity H2 and in a sustainable way. This occurs through two half reactions, that is the Hydrogen Evolution Reaction (HER) and the Oxygen Evolution Reaction (OER). However, the OER is a slow reaction due to the various steps involved in the process. For this reason, there is a great call for the development of nanocatalysts based on earth-abundant metals (Ni, Cu, Co, Fe, Ca) for the OER. Among the most varied types of nanostructures, nanofibers (one-dimensional structures, 1D) are presented as efficient supports for catalysis due to their high surface area. In this work, Solution Blow Spinning (SBS) method was used to produce solid and hollow nanofibers of some metal oxides (Ca3Co4O9-δ, NiO, CuFe2O4, CoFe2O4 e NiFe2O4) based on non-noble metals with potential to be used as electrocatalysts of the OER in alkaline medium. A series of morphological, structural, elemental and electrochemical characterization techniques were performed to provide detailed compression on the influence of morphological parameters on the performance of each catalyst. Hollow fibers with average diameter on range 200 - 257 nm and highly rough surface were obtained. It was observed that the performance for the OER is dependent on the morphological characteristics of these materials (diameter, crystallite size, tubular wall thickness and roughness). With superior activity to 1D, 2D and 3D materials of the same composition reported in the literature. From general results, when compared with nanoparticles, it was concluded that the structure of the fibrillar morphology of nickel-oxide puts an important rule in the overall performance of the electrocatalyst. Also influenced by route of synthesis, which contributed to the formation of a greater amount of active species for the OER on the surface of electrode, reflecting directly in the electrochemically active area (ECSA). Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES O hidrogênio (H2) como combustível tem sido considerado como a mais promissora fonte de energia renovável para suprir a crescente demanda global. Entre os métodos de produção do H2, a eletrólise da água (water splitting, em inglês) é capaz de produzir H2 de alta pureza e de forma sustentável. Isso ocorre através de duas semi-reações, ou seja, a Reação de Evolução do Hidrogênio (HER) e a Reação de Evolução do Oxigênio (OER). No entanto, a OER é uma reação lenta devido às várias etapas envolvidas no processo. Por esse fato, há um grande apelo para o desenvolvimento de nanocatalisadores à base de metais abundantes na terra (Ni, Cu, Co, Fe, Ca) para a OER. Dentre os mais variados tipos de nanoestruturas, as nanofibras (estruturas unidimensionais, 1D) se apresentam como eficientes suportes para catálise devido a sua elevada área superficial. Neste trabalho, o método Solution Blow Spinning (SBS) foi empregado para a produção de nanofibras sólidas e ocas de alguns óxidos metálicos (Ca3Co4O9-δ, NiO, CuFe2O4, CoFe2O4 e NiFe2O4) baseados em metais nãonobres, com potencial para serem usados como eletrocatalisadores da OER em meio alcalino. Uma série de técnicas de caracterização morfológica, estrutural, elementar e eletroquímicas foram realizadas, para fornecer uma compressão detalhada sobre à influência dos parâmetros morfológicos no desempenho de cada catalisador. Fibras ocas com diâmetro médio entre 200 - 257 nm e superfície altamente rugosa foram obtidas. Foi observado que o desempenho para a OER é dependente das características morfológica desses materiais (diâmetro, tamanho de cristalito, espessura da parede tubular e rugosidade). Com atividade superior a materiais 1D, 2D e 3D de mesma composição reportados na literatura. Dos resultados gerais, quando comparado com nanopartículas, concluiu-se que a estrutura da morfologia fibrilar do óxido de níquel coloca uma regra importante no desempenho global do eletrocatalisador. Influenciando também pela rota de síntese, que contribuiu para a formação de uma maior quantidade de espécies ativas para a OER na superfície do eletrodo, refletindo diretamente na área eletroquimicamente ativa (ECSA).