4,208 research outputs found
Collimateur optique pour fibres monomodes, fibre monomode à collimateur intégré et procédé de fabrication
No full textDemandeurs : Chanclou Philippe, Gravey Philippe, Thual Monique, France Télécom ; Date de dépôt : 16/10/2000 ; N° de dépôt : FR20000013245The invention concerns an optical collimator for monomode fibres, characterised in that the collimator comprises a fibre section with mode expansion (S1) and a fibre section with expansion maintenance (S2). The invention is applicable to monomode optical fibres with extended field
A primer on innovation and growth
No full textPhilippe Aghion emphasises that for Europe to stimulate innovation and growth, it is not enough to increase spending on research and development and the protection of intellectual property.
Reconfigurable nodes for passive optical networks (PON)
No full textMestrado em Engenharia Electrónica e TelecomunicaçõesRecentemente , as redes ópticas de nova geração têm sido motivo de acesa
discussão nos meios científicos. Com o aumento verificado nos últimos anos
do numero de utilizadores e o aparecimento de novos serviços disponibilizados
através das redes de acesso, torna-se cada vez mais claro que a fibra óptica é
a única solução para disponibilizar a largura de banda necessária.
Neste trabalho é apresentado um novo método passivo capaz de aumentar os
níveis de escalabilidade e reconfigurabilidade destas redes. O método consiste
no controlo da quantidade de potência de bomba entregue a um amplificador
ou conjunto de amplificadores remotos em série, permitindo o controlo
independentemente do ganho fornecido por cada amplificador.
Utilizando o método proposto consegue-se evitar o uso de componentes
activos, ou mais complexos, para controlo da quantidade de potência de
bomba a fornecer aos amplificadores remotos, tornando o processo de
amplificação simultaneamente passivo e reconfigurável.
Foi também desenvolvido, no âmbito deste trabalho, uma ferramenta de
simulação baseada em algoritmos genéticos, capaz de simular e determinar a
melhor solução para diversos cenários, optimizando os diversos parâmetros.
Foi também realizada a caracterização de uma fibra óptica dopada com érbio,
onde foi estudado o comportamento do ganho da fibra dopada quando
bombeada por um sinal de bomba diferente dos comprimentos de onda
nominais, 980nm e 1480nm. Ainda, o caso de bombeamentos com diferentes
comprimentos de onda multiplexados foi motivo de estudo.
ABSTRACT: Recently, the new generation optical networks are being the focus of several
discussions in the scientific forums. With the observed increase of users in the
last years, and the emergence of new services supplied through the access
networks, it became even clearer that optical fiber is the best solution to provide
the required bandwidth.
In this work it is presented a new passive method capable to improve the
scalability and reconfigurability of those networks. The method consist in
controlling the amount of pump power to be supplied to one or various remotely
pumped optical amplifiers disposed in series, and by this, adjust independently
the gain of each.
Using the proposed method, it is possible to dismiss the use of active or/and
complex components, to control the remote amplifiers conditions, making all
this amplification process passive and reconfigurable.
It was also developed during this work, a simulation tool based in genetic
algorithms, capable to simulate and reach the best solution for different network
scenarios, optimizing the several parameters.
A laboratory characterization of an erbium doped fiber amplifier it was also
performed, where it was studied the gain behaviour of the doped fiber, when it
is pumped by a signal which wavelength is different of the nominal
wavelengths, 980nm and 1480nm. In this characterization it was also studied
the gain behaviour when the amplifier is pumped with multiple multiplexed
pump signals
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Letter to Philippe-Antoine Merlin, 1802 November 12.
No full textLetter to Philippe-Antoine Merlin, concerning a conflict involving charges of plagarism between the author and C. Laucuouque, dated "21 brumaire, an 11." The author's signature is not entirely legible. Accompanying enveloped shows traces of red wax seal
Histoire de la Deuxième Guerre Mondiale (1992-1997) (09). Philippe Burrin (1) - face B
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin
Histoire de la Deuxième Guerre Mondiale (1992-1997) (09). Philippe Burrin (1) - face A
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin
Histoire de la Deuxième Guerre Mondiale (1992-1997) (10). Philippe Burrin (2) - face B
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin (suite)
Histoire de la Deuxième Guerre Mondiale (1992-1997) (10). Philippe Burrin (2) - face A
No full textSéminaire organisé et enregistré par l'IHTP (Paris), entre 1992 et 1997 ; sous la direction de Jean-Pierre Azéma et Dominique Veillon. Communication de Philippe Burrin (suite)
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Episode #7: Philippe Sands, From Genocide to Ecocide
No full textThis special episode of Borderlines features influential educator, commentator, and litigator Philippe Sands discussing ground-breaking efforts to introduce ecocide – the crime of environmental destruction – into international legal arenas. Philippe Sands QC is Professor of Law at University College London, Pisar Visiting Professor of Law at Harvard, and a barrister at Matrix Chambers. He practises as Counsel before international courts and tribunals. His teaching areas include public international law, the settlement of international disputes including arbitration, and environmental and natural resources law. Philippe is the author of many books, including East West Street: On the Origins of Crimes Against Humanity and Genocide (2016) and The Last Colony, forthcoming in September 2022. Philippe recently co-chaired an independent expert panel which proposed in June 2021 that a new, fifth crime of ecocide be adopted into the Rome Statute of the International Criminal Court. In Episode Seven of Borderlines, listeners will learn about the relationship between ecocide and existing crimes, historic legal and political definitions of genocide being played out today, and the role of courts in enforcing awards and judgments against even Goliath polluters and aggressors. Borderlines from Berkeley Law is a podcast about global problems in a world fragmented by national borders. Our host is Katerina Linos, Tragen Professor of International Law and co-director of the Miller Institute for Global Challenges and the Law. </p
A Primer on Innovation and Growth. Bruegel policy brief 2006/06, October 2006
No full textSummary. In sharp contrast with the post-war period, over the last 10 years income per head in the EU has begun to decline in comparison to that of the US. Against this background, the revival of growth and productivity has become an overriding priority of European policymakers. While fostering innovation has become a necessity in Europe, R&D investments alone will not do the job
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