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Tomlow J.,Zittau Gorlitz University of Applied Sciences
International Journal of Space Structures | Year: 2016

Designing and building the stadium complex for the International Olympic Games 1972 in Munich in only five years, may be characterized as a singular challenge. The futuristic and huge tensile structure, covered with Plexiglas became to be designed by engineers and architects of different fields: Günther Behnisch, Frei Otto, Fritz Leonhardt, Jörg Schlaich, John Hadji Argyris, Klaus Linkwitz with Carl Mertz responsible for the management. Based on written reports and testimonials from witnesses of the process, the paper analyses all phases, starting from the skepticism of many that the most spectacular part, the roof, would be buildable. After Leonhardt/Schlaich also Otto/Bubner became part of the design team. At the start of building the engineers registered that the technical models of the Frei Otto team could not bring exact data for (all) cutting patterns, which was a crucial problem. Both Argyris and Linkwitz delivered feasible computational methods for calculating cable lengths and joint locations. The executed result was criticized by its authors for different reasons, in the same time respecting the unique mutual achievement. The spectacular Olympic stadium complex was much appreciated by visitors, and critics ranked it as one of the most impressive and innovative examples of German architecture. © The Author(s) 2016.

Mathe P.,Weierstrass Institute for Applied Analysis And Stochastics | Tautenhahn U.,Zittau Gorlitz University of Applied Sciences
Inverse Problems | Year: 2011

The authors explain how the major results which were obtained recently in Eggermont et al (2009 Inverse Problems 25 115018) can be derived from a more general perspective of recent regularization theory. By pursuing this further, the authors provide a general viewon regularization under general noise assumptions, including weakly and strongly controlled noise. The prospect is not to generalize previous work in this direction, but rather to envision the intrinsic structure present in regularization under general noise assumptions. In particular, the authors find variants of the discrepancy and the Lepskiǐ principle to choose the regularization parameter, albeit within different context and under different assumptions. © 2011 IOP Publishing Ltd.

Bandow C.,Zittau Gorlitz University of Applied Sciences | Bandow C.,BASF | Weltje L.,Biodiversity and Climate Research Center
Science of the Total Environment | Year: 2012

The development of a chronic mollusc toxicity test is a current work item on the agenda of the OECD. The freshwater pond snail Lymnaea stagnalis is one of the candidate snail species for such a test. This paper presents a 21-day chronic toxicity test with L. stagnalis, focussing on embryonic development. Eggs were collected from freshly laid egg masses and exposed individually until hatching. The endpoints were hatching success and mean hatching time. Tributyltin (TBT), added as TBT-chloride, was chosen as model substance. The selected exposure concentrations ranged from 0.03 to 10 μg. TBT/L (all as nominal values) and induced the full range of responses. The embryos were sensitive to TBT (the NOEC for mean hatching time was 0.03 μg. TBT/L and the NOEC for hatching success was 0.1 μg. TBT/L). In addition, data on maximum limit concentrations of seven common solvents, recommended in OECD aquatic toxicity testing guidelines, are presented. Among the results, further findings as average embryonic growth and mean hatching time of control groups are provided. In conclusion, the test presented here could easily be standardised and is considered useful as a potential trigger to judge if further studies, e.g. a (partial) life-cycle study with molluscs, should be conducted. © 2012 Elsevier B.V.

Agency: European Commission | Branch: FP7 | Program: MC-ITN | Phase: FP7-PEOPLE-2012-ITN | Award Amount: 3.58M | Year: 2013

In recent years the computational complexity of mathematical models employed in financial mathematics has witnessed a tremendous growth. Advanced numerical techniques are imperative for the most present-day applications in financial industry. The motivation for this training network is the need for a network of highly educated European scientists in the field of financial mathematics and computational science, so as to exchange and discuss current insights and ideas, and to lay groundwork for future collaborations. Besides a series of internationally recognized researchers from academics, leading quantitative analysts from the financial industry also participate in this network. The challenge lies in the necessity of combining complementary techniques and skills such as mathematical analysis, sophisticated numerical methods and stochastic simulation methods with deep qualitative and quantitative understanding of mathematical models arising from financial markets. The main training objective is to prepare, at the highest possible level, young researchers with a broad scope of scientific knowledge and to teach transferable skills, like social awareness which is very important in view of the recent financial crises. The current topic in this network is that the financial crisis in the European countries is a contagion and herding effect and is clearly outside of the domain of validity of Black-Scholes and Mertons theory, since the market is not Gaussian and it is not frictionless and complete. In this research training network our aim is to deeper understand complex (mostly nonlinear) financial models and to develop effective and robust numerical schemes for solving linear and nonlinear problems arising from the mathematical theory of pricing financial derivatives and related financial products. This aim will be accomplished by means of financial modelling, mathematical analysis and numerical simulations, optimal control techniques and validation of models.

Agency: European Commission | Branch: H2020 | Program: SGA-CSA | Phase: INNOVATION | Award Amount: 193.68K | Year: 2015

The aim of the present proposal is to contribute to the smart growth in the Free State Saxony as an emerging region in the European Union by increasing the efficiency and effectiveness of investments in research, development and innovation and by contributing to a better and more efficient connection of actors along the innovation chain. To achieve the above mentioned objectives the proposed project will: a) Identify bottlenecks to the creation of economic impact in companies benefitting from grants by Horizon2020s SME instrument and address these bottlenecks with the help of capable coaches. This service to beneficiaries of the SME instrument in the context of a giving project is called Key account management (KAM). b) Increase the efficiency and effectiveness of innovation processes in small and medium sized enterprises with significant innovation activities that could potentially become beneficiaries of European support to research and innovation but would not have effective access to consulting services for innovation management. This service, which will be provided independently from a specific innovation project and focussing on a companys innovation management system, is called Enhancing the innovation management capacity of SMEs (EIMC). The project targets at the delivery of in total twenty 7-days service packages, five KAM and 15 EIMC services, in the geographical area of the Free State Saxony (Germany).

Muche T.,Zittau Gorlitz University of Applied Sciences
Applied Energy | Year: 2014

Pump storage plants are an important electricity storage technology at present. Investments in this technology are expected to increase. The necessary investment valuation often includes expected cash flows from future price-based unit commitment policies. A price-based unit commitment policy has to consider market price uncertainty and the information revealing nature of electricity markets. For this environment stochastic programming models are suggested to derive the optimal unit commitment policy. For the considered day-ahead price electricity market stochastic and deterministic unit commitment policies are comparable suggesting an application of easier implementable deterministic models. In order to identify suitable unit commitment and forecasting policies, deterministic unit commitment models are applied to actual day-ahead electricity prices of a whole year. As a result, a robust forecasting model should consider the unit commitment planning period. This robust forecasting models result in expected cash flows similar to realized ones allowing a reliable investment valuation. © 2013 Elsevier Ltd.

Lassig J.,Zittau Gorlitz University of Applied Sciences | Sudholt D.,University of Sheffield
Evolutionary Computation | Year: 2014

We present a general method for analyzing the runtime of parallel evolutionary algorithms with spatially structured populations. Based on the fitness-level method, it yields upper bounds on the expected parallel runtime. This allows for a rigorous estimate of the speedup gained by parallelization. Tailored results are given for common migration topologies: ring graphs, torus graphs, hypercubes, and the complete graph. Example applications for pseudo-Boolean optimization show that our method is easy to apply and that it gives powerful results. In our examples the performance guarantees improve with the density of the topology. Surprisingly, even sparse topologies such as ring graphs lead to a significant speedup for many functions while not increasing the total number of function evaluations by more than a constant factor. We also identify which number of processors lead to the best guaranteed speedups, thus giving hints on how to parameterize parallel evolutionary algorithms. © 2014 by the Massachusetts Institute of Technology.

Lassig J.,Zittau Gorlitz University of Applied Sciences | Sudholt D.,University of Sheffield
Soft Computing | Year: 2013

Parallelization is becoming a more important issue for solving difficult optimization problems. Island models combine phases of independent evolution with migration where genetic information is spread out to neighbored islands. This can lead to an increased diversity within the population. Despite many successful applications, the reasons behind the success of island models are not well understood. We perform a first rigorous runtime analysis for island models and construct a function where phases of independent evolution as well as communication among the islands are essential. A simple island model with migration finds a global optimum in polynomial time, while panmictic populations as well as island models without migration need exponential time, with very high probability. Our results lead to new insights into the usefulness of migration, how information is propagated in island models, and how to set parameters such as the migration interval. This is a novel contribution to the theoretical foundation of parallel EAs. Further, we provide empirical results that complement the theoretical results, investigate the robustness with respect to the choice of the migration interval and compare various migration topologies using statistical tests. © 2013 Springer-Verlag Berlin Heidelberg.

Liao Y.,University of Bristol | Weber J.,Zittau Gorlitz University of Applied Sciences | Faul C.F.J.,University of Bristol
Macromolecules | Year: 2015

Carbon dioxide (CO2) capture from point sources like coal-fired power plants is a potential solution for stabilizing atmospheric CO2 content to avoid global warming. Sorbents with high and reversible CO2 uptake, high CO2 selectivity, good chemical and thermal stability, and low cost are desired for the separation of CO2 from N2 in flue or natural gas. We report here, for the first time, on the synthesis of new microporous polyimide (PI) networks from the condensation of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) and 1,3,5-triazine-2,4,6-triamine (melamine) using a Lewis acid catalyst zinc acetate/imidazole complex. These PI network materials, prepared in the absence and presence of dimethyl sulfoxide (DMSO) as weak solvent template, exhibit strong fluorescence. Nitrogen-containing carbons can be accessed from our PI networks via a simple thermal pyrolysis route. The successful construction of new microporous PI networks and derived N-containing carbons is shown here to provide promising CO2 sorbents with high uptake capacities (15 wt %) combined with exceptional selectivities over N2 (240), while their fluorescent properties can be exploited for simple sensing. © 2015 American Chemical Society.

Liao Y.,University of Bristol | Weber J.,Zittau Gorlitz University of Applied Sciences | Faul C.F.J.,University of Bristol
Chemical Communications | Year: 2014

Conjugated microporous polytriphenylamine networks with surface areas of 530 m2 g-1 were synthesized via Buchwald-Hartwig coupling, resulting in high CO2 uptake (up to 6.5 wt%) and CO 2-N2 selectivity (75) at 1 bar and 303 K. © the Partner Organisations 2014.

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