Time filter

Source Type

Izzo D.,European Space Agency | Weiss N.,Technical University of Delft | Seidl T.,Gelsenkirchen University of Applied Sciences
Journal of Guidance, Control, and Dynamics | Year: 2011

Neuromorphic architectures to robust and adaptive navigation based on visual clues have been proposed as automated landing systems. In particular, constant-optic-flow descents have been studied in relation to their bioinspired nature and to their promise for a substantial hardware and software simplification. The main body of work on the topic considers Earth-based systems as applications, such as micro air vehicles, and has only lately looked at planetary landings, but never in relation to their mass optimality. In this paper, constant-optic-flow descents are studied with respect to optimality, first from a theoretical point of view using Pontryagin's maximum principle and then performing a numerical investigation on some selected cases (Apollo-like) and a comparison with unconstrained descents. The propellant mass introduced by forcing a constant optic flow during a lunar descent is estimated for typical high-gate/low-gate conditions. The effect of constraining the spacecraft pitch law during the constant-optic-flow descent is also studied, showing that an optimal pitch law is essential to lower the overall mass consumption and that linear or exponential laws may not be adequate. A guidance algorithm is then presented and discussed for use in automated planetary landing when a constant optic flow is regulated. Copyright © 2011 by Dario Izzo. Source

Zhong M.,Beihang University | Ding S.X.,University of Duisburg - Essen | Ding E.L.,Gelsenkirchen University of Applied Sciences
Automatica | Year: 2010

This paper deals with the problem of observer-based fault detection for linear discrete time-varying (LDTV) systems. A problem formulation is first proposed to address the optimization of the fault detection filter (FDF) design, which is expressed in terms of maximizing a finite horizon H ∞/H∞ or H-/H∞ performance index. This formulation can be applied to FDF design of LDTV systems subject to l2-norm bounded unknown inputs or stochastic noise sequences. It is shown that a unified optimal solution to the FDF can be obtained by solving the discrete time Riccati equation and the optimal FDF is not unique. A numerical example is given to illustrate the proposed method. © 2010 Elsevier Ltd. All rights reserved. Source

Marginean G.,Gelsenkirchen University of Applied Sciences | Utu D.,Polytechnic University of Timisoara
Applied Surface Science | Year: 2012

High velocity oxygen fuel (HVOF) spraying method was used in order to obtain very dense and good adhesive CoNiCrAlY-coatings deposited onto nickel-based alloy. The coatings were differently treated (preoxidized, vacuum treated or electron beam irradiated) before their exposure to cyclic oxidation tests in air at 1000 °C for periods up to 5 h. Changes of the coatings morphology and structure were analysed by scanning electron microscopy (SEM) and X-ray diffraction technique (XRD). The surface temperature of the samples was measured during cooling, between the oxidation cycles, and finally was associated with the thickness of the grown protective oxide scale on the CoNiCrAlY-surface. The experimental results demonstrated that depending on the thickness respectively on the different structures of the grown oxide scale, the cooling rate of the sample surface will be different as well. © 2012 Elsevier B.V. All rights reserved. Source

Agency: Cordis | Branch: FP7 | Program: CP-IP | Phase: SSH.2012.3.1-1 | Award Amount: 7.43M | Year: 2013

The starting point for MOPACT is the ambitious goals set by Horizon 2020 and the European Innovation Partnership Pilot Project on Active and Healthy Ageing (EIPAHA). Our response is ambitious too: we aim to provide the research and practical evidence upon which Europe can make longevity an asset for social and economic development. MOPACT will create a high quality, multi-disciplinary critical mass of leading researchers and, in the closest possible partnership with stakeholders and through a carefully planned iterative process, build a compendium of essential state-of-the-art and foresight intelligence upon which to develop the policy, practice, service and product developments and innovations required to meet the goals of Horizon 2020 and, in particular, the EIPAHA. Active and healthy ageing is the primary focus of MOPACT and it will build on the momentum created by EY2012.

Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: SSH.2013.1.1-1 | Award Amount: 3.03M | Year: 2014

SIMPACT advances understanding of social innovations economic dimensions, creating new concepts, models and instruments for policy makers, innovators, investors and intermediaries. It systematically investigates how social innovations can enable the most vulnerable in society to become economic assets, integrating critical analysis of current and previous work with future-oriented methodologies, new actionable knowledge and continual stakeholder participation. SIMPACTs multidisciplinary mixed-method approach advances knowledge and the state of the art by (i) elaborating a theoretical model of the economic dimensions of social innovation throughout its lifecycle; (ii) generating new empirical knowledge on the economic dimensions through rich, theoretically informed analysis of successful and less successful cases; (iii) analysing drivers and barriers shaping the economic impact of social innovations, and levers for their scaling and diffusion; (iv) developing indicators to measure social innovations and tailored methods to evaluate social and economic impact; (v) enhancing modes of public policy production, instruments and guidelines; (vi) generating foresight knowledge through agent-based modelling and scenario building. SIMPACT integrates theoretical, empirical and actionable knowledge to create evidence-based approaches to business development, public policy and research. A participatory research approach actively engages policy makers, innovators, investors and intermediaries of vulnerable groups. Action learning, indicator labs and stakeholder experiments facilitate processes of co-creation, stimulating shared learning, strengthening practitioner knowledge and enhancing conceptualisation of the economic base. Partners understanding of welfare regime diversity, including New Member State specificities, will ensure tailored, actionable deliverables. Eight high profile associate partners will help ensure the success of SIMPACTs dissemination activities.

Discover hidden collaborations