Organisation indienne pour la recherche spatiale

Résumé

L'Indian Space Research Organisation (ISRO, Organisation indienne de recherche spatiale en français) est l'agence spatiale de l'Inde. Elle est la principale organisation indienne chargée de mettre en œuvre le programme spatial de l'Inde en concevant et en exploitant les satellites et les lanceurs nationaux. Historique L'ISRO, rattachée au département des sciences spatiales, est créée en 1969 pour fédérer l'activité spatiale. Activité L'ISRO intervient sur l'ensemble du périmètre spatial avec toutefois une part prépondérante accordée à la réalisation des lanceurs et des satellites d'applications :

Lanceurs : PSLV et GSLV.
Satellites d'application : ** Satellites d'observation de la Terre Indian Remote Sensing satellite (IRS). ** Satellites de télécommunications et de météorologie Indian National Satellite System (INSAT). ** Autres satellites avec une vocation en partie scientifique en coopération avec le CNES pour l'étude du climat Megha-Tropiques et SAR

Source officielle

https://fr.wikipedia.org/wiki/Organisation_indienne_pour_la_recherche_spatiale

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Roadmap on multimode light shaping

Jérôme Faist, Tobias Kippenberg, Marco Piccardo

Our ability to generate new distributions of light has been remarkably enhanced in recent years. At the most fundamental level, these light patterns are obtained by ingeniously combining different electromagnetic modes. Interestingly, the modal superposition occurs in the spatial, temporal as well as spatio-temporal domain. This generalized concept of structured light is being applied across the entire spectrum of optics: generating classical and quantum states of light, harnessing linear and nonlinear light-matter interactions, and advancing applications in microscopy, spectroscopy, holography, communication, and synchronization. This Roadmap highlights the common roots of these different techniques and thus establishes links between research areas that complement each other seamlessly. We provide an overview of all these areas, their backgrounds, current research, and future developments. We highlight the power of multimodal light manipulation and want to inspire new eclectic approaches in this vibrant research community.

IOP Publishing Ltd2022

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Switzerland has a small but internationally recognised set of competences and actors in fuel cells and hydrogen, from fundamental research to technology and product development. Swiss organisations are prominent in a number of research partnerships, and some have either major international co-operation or are partly or fully owned by overseas companies. However, the sector in Switzerland remains somewhat fragmented, with many actors pursuing their own niches and relatively little cross-fertilisation or co-ordination. While companies can and do work directly with research organisations, the sector (and possibly the country) have not proven large enough to build or support more connected value or supply chains. The Swiss Federal Office of Energy, in conjunction with other Swiss support organisations, provides funding for both research and development, and some for demonstration projects. It is generally well regarded and considered flexible and simple to deal with. It does not itself have a grand vision for how the sector could or should develop, typically being responsive to project suggestions. Such a vision is not necessarily part of its remit, but does seem to reflect a broader absence of strategic perspective regarding the fuel cell and hydrogen sector in Swiss energy policy and energy debate. This project set out to understand the state of the fuel cell and hydrogen sector in Switzerland, primarily through interviews with relevant players, and put it into the context of global developments, through E4tech’s industry knowledge and further research. An additional goal was to identify any major gaps or barriers to sector development, and to suggest options for closing the gaps or removing the barriers.

E4tech2014

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On board of satellites traditionally Travelling Wave Tube Amplifiers (TWTAs) together with standard waveguide technology were used for transmitters in telecommunication payload systems. With the advent of Solid State Power Amplifiers (SSPAs) printed circuit board (PCB) technology became also attractive for the output stages of these high-power transmitters with the advantage of smaller size, lower weight and higher integration density. In a power combining circuitry the PCBs have to be interconnected by phase stable coaxial cable assemblies with suited connectors. Although SMA RF connectors are preferred in space telecom missions because of their light weight and small size this type of connector has serious limitations in terms of the required RF power handling. Therefore in these high power sections, one is still forced to use the often bulky TNC connectors. Under the ESA activity ”High Power SMA Connectors” a European consortium has been created for the investigation of small size high power coaxial connectors that will be optimized with regard to RF-breakdown, Corona, Multipactor and PIM effects as well as thermal power dissipation making them applicable in satellite transmitter stages. The goal is the development of a new family of high power SMA connectors capable to withstand power levels of at least 50W CW in space environment to match the levels delivered by the new generation of Solid State Power Amplifiers. The research is manifold: First, suitable theories of PIM, corona discharge und multipactor in coaxial structures have to be established or adapted from known similar (waveguide) problems. Second, the power limiting effects in SMA connectors like the internal air gap have to be identified and eliminated by appropriate changes of the connector design. Third, suitable materials for the individual parts and the manufacturing process of the new high power SMA connectors have to be analysed and selected. The activity started with a deep literature research of the state of the art of the interesting phenomena followed by first suggestions of the basic design of a high power SMA connector. At the workshop we will report on the status of the project and on the achieved results.

2008

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2008