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According to the European Space Agency (ESA) Lunar Exploration program, the use of GNSS weak-signal navigation in future lunar exploration missions has the potential to increase the robustness of the navigation during all mission phases and improve considerably its autonomy. The major objectives of the ESA Moon-GNSS project have been to determine the feasibility of using GNSS (GPS/Galileo) weak-signal technology in future lunar missions to improve the navigation performance in terms of accuracy, cost reduction and autonomy. The Moon mission scenario is very challenging for the GNSS signals processing: less visibility compared to an Earth-based receiver, low signal strength, poor satellite geometry, Earth and Moon signal occultation, and spacecraft dynamics. The identification of the Moon-GNSS navigation receiver requirements for the upcoming lunar exploration missions has been performed. The impact of the receiver requirements on the Moon-GNSS receiver module architecture and algorithms has been analyzed (weak signal processing, filtering and navigation), including an overview of the state of the art space-borne GNSS receivers. Besides, the synergies between GNSS signal/navigation processing and other navigation sensors (i.e. accelerometers, optical camera, laser altimeter) have been analyzed, using the state of the art of sensors integration for space missions. A demonstrator of the weak-signal Moon-GNSS navigation has been designed and implemented, showing the main functional and performance capabilities of the Moon-GNSS receiver. A test campaign representative of a real Moon-GNSS mission has been carried out, covering all the mission phases of the real mission conditions in terms of dynamics and signal disturbances, for different configurations: standard sensors, standard sensors plus GNSS and stand-alone GNSS navigation. Keywords 1 -GNSS weak-signals, Moon missions, navigation, Proof of Concept I. MOON-GNSS SCENARIO DESCRIPTION In order to analyze and identify, the Moon-GNSS navigation receiver requirements, the first task has been to define the Moon-GNSS scenario to be used as the reference scenario for the Moon-GNSS activity. The selected Moon-GNSS reference scenario is based on the ESA Lunar Lander mission, with landing site near Moon's South Pole. The different mission phases of the Moon-GNSS reference trajectory are listed below: 1 This work was supported by the ESA project 4000107112/12/NL/AF/fk.

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Tailoring assistive systems for guiding and monitoring an individual in daily living activities is a complex task. This paper presents ALI, an assistive system combining a formal possibilistic argumentation system and an informal model of human activity: the Cultural-Historic Activity Theory, facilitating the delivery of tailored advices to a human actor. We follow an activity-centric approach, taking into consideration the human's motives, goals and prioritized actions. ALI tracks a person in order to I) determine what activities were performed over a period of time (activity recognition tracking), and II) send personalized notifications suggesting the most suitable activities to perform (decision-making monitoring). The ALI system was evaluated in a formative pilot study related to promote social activities and physical exercise.

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