8 research outputs found

    Quantifying the Partial Volume Effect in PET Using Benford's Law

    Full text link

    The partial volume effect in PET/SPECT and Benford's Law

    No full text

    Quantifying the partial volume effect in PET using Benford's Law

    No full text

    An in-orbit active debris removal mission - REMOVEDEBRIS: Pre-Launch update

    Get PDF
    International audienceSince the beginning of the space era, a huge amount of debris has progressively been generated. Most of the objects launched into space are still orbiting the Earth and today these objects represent a threat as the presence of space debris incurs risk of collision and damage to operational satellites. A credible solution has emerged over the recent years: actively removing debris objects by capturing them and disposing of them. This paper provides an update to the mission baseline and concept of operations of the EC FP7 RemoveDEBRIS mission drawing on the expertise of some of Europe's most prominent space institutions in order to demonstrate key active debris remove (ADR) technologies in a low-cost ambitious manner. The mission will consist of a microsatellite platform (chaser) that ejects 2 CubeSats (targets). These targets will assist with a range of strategically important ADR technology demonstrations including net capture, harpoon capture and vision-based navigation using a standard camera and LiDAR. The chaser will also host a drag sail for orbital lifetime reduction. The mission baseline has been revised to take into account feedback from international and national space policy providers in terms of risk and compliance and a suitable launch option is selected. A launch in late 2016 is targeted. The payload flight models are currently scheduled to be delivered in late 2015 for platform integration (AIT) and subsequent EVT phases in early 2016. The RemoveDEBRIS mission aims to be one of the world's first in-orbit demonstrations of key technologies for active debris removal and is a vital prerequisite to achieving the ultimate goal of a cleaner Earth orbital environment

    REMOVEDEBRIS: An In-Orbit Active Debris Removal Demonstration Mission

    Get PDF
    International audienceSince the beginning of the space era, a significant amount of debris has progressively been generated. Most of the objects launched into space are still orbiting the Earth and today these objects represent a threat as the presence of space debris incurs risk of collision and damage to operational satellites. A credible solution has emerged over the recent years: actively removing debris objects by capturing them and disposing of them. This paper provides an update to the mission baseline and concept of operations of the EC FP7 RemoveDEBRIS mission drawing on the expertise of some of Europe's most prominent space institutions in order to demonstrate key active debris remove (ADR) technologies in a low-cost ambitious manner. The mission will consist of a microsatellite platform (chaser) that ejects 2 CubeSats (targets). These targets will assist with a range of strategically important ADR technology demonstrations including net capture, harpoon capture and vision-based navigation using a standard camera and LiDAR. The chaser will also host a drag sail for orbital lifetime reduction. The mission baseline has been revised to take into account feedback from international and national space policy providers in terms of risk and compliance and a suitable launch option is selected. A launch in 2017 is targeted. The RemoveDEBRIS mission aims to be one of the world's first in-orbit demonstrations of key technologies for active debris removal and is a vital prerequisite to achieving the ultimate goal of a cleaner Earth orbital environment

    REMOVEDEBRIS: An EU low cost demonstration mission to tet ADR technologies

    Get PDF
    International audienceRemoveDEBRIS is aimed at performing key Active Debris Removal (ADR) technology demonstrations (e.g capture, deorbiting) representative of an operational scenario during a low-cost mission using novel key technologies for ADR. The project is based on and aimed at contributing to global European ADR roadmaps. A microsatellite called here RemoveSAT, will release, capture and deorbit two space debris targets, called DebriSATs, in sequence using various rendezvous, capture and deorbiting technologies thus demonstrating in orbit, key ADR technologies for future missions in what promises to be the first ADR technology mission internationally. The debris objects themselves in this case will be released by the main satellite with subsequent recapture. Although this is not a fully-edged ADR mission, the project is an important step towards a fully operational ADR mission. The ultimate goal of this activity is to protect space assets from space debris and to minimize the collision risk of current and future space missions as the FP7 call for space calls for. The mission proposed in this project and the subsequent technology developments, is a vital prerequisite to achieve this ultimate goal of a cleaner Earth orbital environment. The mission proposed by the RemoveDEBRIS project will be such a demonstration mission -the world's first, and perhaps the most important demonstration of ADR to date -and the technologies that will be developed under the project have been strategically selected for their importance in future ADR activities
    corecore