ERC FUNDED PROJECTS

Standard spacecraft designs comprise modules assembled in a single monolithic structure. When unexpected situations occur, the spacecraft are unable to adequately respond, and significant functional and financial losses are unavoidable. For instance, if the payload of a spacecraft fails, the whole system becomes unserviceable and substitution of the entire spacecraft is required. It would be much easier to replace the payload module only than launch a completely new satellite. This idea gives rise to an emerging concept in space engineering termed disaggregated spacecraft. Disaggregated space architectures (DSA) consist of several physically-separated modules, interacting through wireless communication links to form a single virtual platform. Each module has one or more pre-determined functions: Navigation, attitude control, power generation and payload operation. The free-flying modules, capable of resource sharing, do not have to operate in a tightly-controlled formation, but are rather required to remain in bounded relative position and attitude, termed cluster flying. DSA enables novel space system architectures, which are expected to be much more efficient, adaptable, robust and responsive. The main goal of the proposed research is to develop beyond the state-of-the-art technologies in order to enable operational flight of DSA, by (i) developing algorithms for semi-autonomous long-duration maintenance of a cluster and cluster network, capable of adding and removing spacecraft modules to/from the cluster and cluster network; (ii) finding methods so as to autonomously reconfigure the cluster to retain safety- and mission-critical functionality in the face of network degradation or component failures; (iii) designing semi-autonomous cluster scatter and re-gather maneuvesr to rapidly evade a debris-like threat; and (iv) validating the said algorithms and methods in the Distributed Space Systems Laboratory in which the PI serves as a Principal Investigator.

1 500 000 €

Start date: 2011-10-01, End date: 2016-09-30

The theory of games played on graphs provides the mathematical foundations to study numerous important problems in branches of mathematics, economics, computer science, biology, and other fields. One key application area in computer science is the formal verification of reactive systems. The system is modeled as a graph, in which vertices of the graph represent states of the system, edges represent transitions, and paths represent behavior of the system. The verification of the system in an arbitrary environment is then studied as a problem of game played on the graph, where the players represent the different interacting agents. Traditionally, these games have been studied either with Boolean objectives, or single quantitative objectives. However, for the problem of verification of systems that must behave correctly in resource-constrained environments (such as an embedded system) both Boolean and quantitative objectives are necessary: the Boolean objective for correctness specification and quantitative objective for resource-constraints. Thus we need to generalize the theory of graph games such that the objectives can express combinations of quantitative and Boolean objectives. In this project, we will focus on the following research objectives for the study of graph games with quantitative objectives: (1) develop the mathematical theory and algorithms for the new class of games on graphs obtained by combining quantitative and Boolean objectives; (2) develop practical techniques (such as compositional and abstraction techniques) that allow our algorithmic solutions be implemented efficiently to handle large game graphs; (3) explore new application areas to demonstrate the application of quantitative graph games in diverse disciplines; and (4) develop the theory of games on graphs with infinite state space and with quantitative objectives. since the theory of graph games is foundational in several disciplines, new algorithmic solutions are expected.

1 163 111 €

Start date: 2011-12-01, End date: 2016-11-30

We propose to take the experimental investigation of strongly-correlated quantum matter in the context of ultracold gases to the next scientific level by applying “quantum gas microscopy” to quantum many-body systems with tunable interactions. Tunability, as provided near Feshbach resonances, has recently proven to be a key ingredient for a broad variety of strongly-correlated quantum gas phases with strong repulsive or attractive interactions and for investigating quantum phase transitions beyond the Mott-Hubbard type. Quantum gas microscopy, as recently demonstrated in two pioneering experiments, will be combined with tunability as given by bosonic Cs atoms to give direct access to spatial correlation functions in the strongly interacting regimes of e.g. the Tonks gases, to open up the atom-by-atom investigation of transport properties, and to allow the detection of entanglement. It will provide local control at the quantum level in a many-body system for entropy engineering and defect manipulation. It will allow the generation of random potentials that add to a periodic lattice potential for the study of glass phases and localization phenomena. In a second step, we will add bosonic and fermionic potassium (39-K and 40-K) to the apparatus to greatly enhance the capabilities of the tunable quantum gas microscope, opening up microscopy to fermionic and, in a third step, to fermionic dipolar systems of KCs polar ground-state molecules. In the case of atomic 40-K fermions with tunable contact interactions, the central goal will be to investigate magnetic systems, in particular to create anti-ferromagnetic many-body states. The Cs sample, for which we routinely achieve ultralow temperatures and extremely pure Bose-Einstein condensates, would serve as a perfect coolant and probe. With KCs, which is non-reactive and hence stable, we will enter a qualitatively new regime of fermionic systems with long-range dipolar interactions.

1 477 500 €

Start date: 2012-01-01, End date: 2016-12-31

Photovoltaics and liquid fuels are poised as major contributors to the global energy market, promising cleaner, renewable sources of energy than fossil fuels. However, the technologies required to make this possibility a reality are limited by their high cost per kWh, and current share of photovoltaics and liquid fuels in the energy market is thus extremely small. One method of reducing the costs of photovoltaics lies in the use of semiconductor nanocrystals to absorb and convert solar photon energy to usable electricity and liquid fuel. Among the advantages of a nanocrystal-based design for photovoltaics are the requirement for thinner absorbing layers, the less energy-intensive refining processes, and their scalability with respect to photovoltaic production. To address these challenges, I plan to initiate a multidisciplinary research project that comprises three separate, but interrelated and complementary, parts that will be conducted in parallel. The first and the main part will be the preparation of novel hybrid nanostructures that have potential for PV and fuel cells applications. The second will focus on a systematic study of the fundamental processes of charge dynamics in the nanoscale regime. The materials and knowledge generated can then be applied in the third part of the project—development of PV and photoelectrochemical devices with scale-up potential for large-scale solar energy exploitation, and examination of benchmark properties (overall efficiency, I V characteristics, external quantum efficiency, hydrogen and liquid fuel production) of our new hybrid materials and devices. These properties will be used as feedback for the synthesis of more complex hybrid structures and for improving our device assembly methods and the choice of materials and/or composites for the devices.

1 500 000 €

Start date: 2011-10-01, End date: 2016-09-30