High-sensitive Optical Pulse-Shape Characterization using a Beating-Contrast-Measurement Technique

Ultrahigh-speed optical transmission technology, such as optical time domain multiplexing or optical signal processing is a key point for increasing the communication capacity. The system performances are strongly related to pulse properties. We present an original method dedicated to short pulse-shape characterization with high repetition rate using standard optical telecommunications equipments. Its principle is based on temporal measurement of the contrast produced by the beating of two delayed optical pulses in a highbandwidth photodetector. This technique returns firstly reliable informations on the pulse-shape, such as pulsewidth, shape and pedestal. Simulation and experimental results evaluate the high-sensitivity and the high-resolution of the technique allowing the measurement of pulse extinction ratio up to 20 dB with typical timing resolution of about 100 fs. The compatibility of the technique with high repetition rate pulse measurement offers an efficient tool for short pulse analysis

Uses of ecosystem services provided by MPAs: how much do they impact the local economy?

Though the basic purpose of MPAs is marine ecosystem conservation, the question of their influence on the local economy is often critical since it governs their social acceptability. This paper addresses the problem of measuring the local economic impact of MPAs, on the basis of a comparative analysis of socio-economic field surveys of 14 case studies in Southern Europe. The surveys were performed in 2005 and 2006 within the framework of the EU funded multidisciplinary EMPAFISH research project. They cover a range of uses of ecosystem services related to the MPA: fishing (commercial and recreational), as well as non-extractive recreational activities (scuba-diving and snorkelling). More than 4,000 questionnaires were filled, providing information on behaviours and attitudes of users, as well as on the economic dimension of their activity. One of the issue is to separate the "reserve effect" from the "site effect"

Borexino : geo-neutrino measurement at Gran Sasso, Italy

Geo-neutrinos, electron anti-neutrinos produced in beta-decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet's interior. After a brief introduction of the geo-neutrinos' properties and of the main aims of their study, we discuss the features of a detector which has recently provided breakthrough achievements in the field, Borexino, a massive, calorimetric liquid scintillator detector installed at the underground Gran Sasso Laboratory. With its unprecedented radiopurity levels achieved in the core of the detection medium, it is the only experiment in operation able to study in real time solar neutrino interactions in the challenging sub-MeV energy region. Its superior technical properties allowed Borexino also to provide a clean detection of terrestrial neutrinos. Therefore, the description of the characteristics of the detected geo-neutrino signal and of the corresponding geological implications are the main core of the discussion contained in this work

Uses of ecosystem services provided by MPAs: how much do they impact the local economy?

International audienceThough the basic purpose of MPAs is marine ecosystem conservation, the question of their influence on the local economy is often critical since it governs their social acceptability. This paper addresses the problem of measuring the local economic impact of MPAs, on the basis of a comparative analysis of socio-economic field surveys of 14 case studies in Southern Europe. The surveys were performed in 2005 and 2006 within the framework of the EU funded multidisciplinary EMPAFISH research project. They cover a range of uses of ecosystem services related to the MPA: fishing (commercial and recreational), as well as non-extractive recreational activities (scuba-diving and snorkelling). More than 4,000 questionnaires were filled, providing information on behaviours and attitudes of users, as well as on the economic dimension of their activity. One of the issue is to separate the "reserve effect" from the "site effect"

Application of phase averaging method for measuring kites performance: onshore results

International audienceThis paper describes an experimental setup aiming to control and measure performances of small leading edge inflatable tube kites, with surface area of less than 35 m². This setup can be deployed either onshore or on a dedicated boat. This article focuses on the onshore results. A 3D load cell is used to obtain the position of the kite under a straight-line assumption. A wind profiler (SODAR) is deployed to determine the wind speed and direction at the kite position. A specific post-processing of the data is presented, including phase averaging. The guideline of this work is to estimate the variation of the aerodynamic lift coefficient and lift to drag ratio along figure-of-eight trajectories. Results, for a chosen particular case, show a decrease of lift coefficient of about 20% of the maximum value during turning maneuvers of the kite. The lift to drag ratio evolution along a trajectory is also observed to go through a local minimum during turning maneuvers of the kite in this case. Influence of weight and inertia is highlighted introducing a point mass model of the kite and tethers. Buckling phenomena of the kite inflatable leading edge tube are highlighted and it is shown that they cause control problems

Borexino: geo-neutrino measurement at Gran Sasso, Italy

International audienceGeo-neutrinos, electron anti-neutrinos produced in β-decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet's interior. After a brief introduction of the geo-neutrinos' properties and of the main aims of their study, we discuss the features of a detector which has recently provided breakthrough achievements in the field, Borexino, a massive, calorimetric liquid scintillator detector installed at the underground Gran Sasso Laboratory. With its unprecedented radiopurity levels achieved in the core of the detection medium, it is the only experiment in operation able to study in real time solar neutrino interactions in the challenging sub-MeV energy region. Its superior technical properties allowed Borexino also to provide a clean detection of terrestrial neutrinos. Therefore, the description of the characteristics of the detected geo-neutrino signal and of the corresponding geological implications are the main core of the discussion contained in this work

Uses of ecosystem services provided by MPAs: How much do they impact the local economy? A southern Europe perspective

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Borexino: Geo-neutrino measurement at Gran Sasso, Italy

Geo-neutrinos, electron anti-neutrinos produced in b-decays of naturally occurring radioactive isotopes in the Earth, are a unique direct probe of our planet\u2019s interior. After a brief introduction of the geo-neutrinos\u2019 properties and of the main aims of their study, we discuss the features of a detector which has recently provided breakthrough achievements in the field, Borexino, a massive, calorimetric liquid scintillator detector installed at the underground Gran Sasso Laboratory. With its unprecedented ra-diopurity levels achieved in the core of the detection medium, it is the only experiment in operation able to study in real time solar neutrino interactions in the challenging sub-MeV energy region. Its superior technical properties allowed Borexino also to provide a clean detection of terrestrial neutrinos. Therefore, the description of the characteristics of the detected geo-neutrino signal and of the corresponding geological implications are the main core of the discussion contained in this work