@article{HuckPoghossianWagneretal.2012,
  author    = {Huck, Christina and Poghossian, Arshak and Wagner, Patrick and Sch{\"o}ning, Michael Josef},
  title     = {Combined amperometric/field-effect sensor for the detection of dissolved hydrogen},
  series = {Sensors and actuators B: Chemical},
  volume    = {187},
  journal   = {Sensors and actuators B: Chemical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0925-4005},
  doi       = {10.1016/j.snb.2012.10.050},
  pages     = {168 -- 173},
  year      = {2012},
  abstract  = {Real-time and reliable monitoring of the biogas process is crucial for a stable and efficient operation of biogas production in order to avoid digester breakdowns. The concentration of dissolved hydrogen (H₂) represents one of the key parameters for biogas process control. In this work, a one-chip integrated combined amperometric/field-effect sensor for monitoring the dissolved H₂ concentration has been developed for biogas applications. The combination of two different transducer principles might allow a more accurate and reliable measurement of dissolved H₂ as an early warning indicator of digester failures. The feasibility of the approach has been demonstrated by simultaneous amperometric/field-effect measurements of dissolved H₂ concentrations in electrolyte solutions. Both, the amperometric and the field-effect transducer show a linear response behaviour in the H₂ concentration range from 0.1 to 3\% (v/v) with a slope of 198.4 ± 13.7 nA/\% (v/v) and 14.9 ± 0.5 mV/\% (v/v), respectively.},
  language  = {en}
}
@article{Weigand2012,
  author    = {Weigand, Christoph},
  title     = {Statistical Tests Based on Reliability and Precision},
  series = {Economic Quality Control : EQC ; international journal for quality and reliability},
  volume    = {27},
  journal   = {Economic Quality Control : EQC ; international journal for quality and reliability},
  number    = {1},
  publisher = {De Gruyter},
  address   = {Berlin},
  issn      = {1869-6147},
  doi       = {10.1515/eqc-2012-0002},
  pages     = {43 -- 64},
  year      = {2012},
  abstract  = {The construction of a statistical test is investigated which is based only on "reliability" and "precision" as quality criteria. The reliability of a statistical test is quantifiedin a straightforward way by the probability that the decision of the test is correct. However, the quantification of the precision of a statistical test is not at all evident. Thereforethe paper presents and discusses several approaches. Moreover the distinction of "nullhypothesis" and "alternative hypothesis" is not necessary any longer.},
  language  = {en}
}
@article{FateriHoetterGebhardt2012,
  author    = {Fateri, Miranda and H{\"o}tter, Jan-Steffen and Gebhardt, Andreas},
  title     = {Experimental and Theoretical Investigation of Buckling Deformation of Fabricated Objects by Selective Laser Melting},
  series = {Physics Procedia},
  volume    = {39},
  journal   = {Physics Procedia},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1875-3892},
  doi       = {10.1016/j.phpro.2012.10.062},
  pages     = {464 -- 470},
  year      = {2012},
  abstract  = {Although Selective Laser Melting (SLM) process is an innovative manufacturing method, there are challenges such as inferior mechanical properties of fabricated objects. Regarding this, buckling deformation which is caused by thermal stress is one of the undesired mechanical properties which must be alleviated. As buckling deformation is more observable in hard to process materials, silver is selected to be studied theoretically and experimentally for this paper. Different scanning strategies are utilized and a Finite Element Method (FEM) is applied to calculate the temperature gradient in order to determine its effect on the buckling deformation of the objects from experiments.},
  language  = {en}
}
@article{HasanKeilStaatetal.2012,
  author    = {Hasan, Istabrak and Keil, Ludger and Staat, Manfred and Wahl, Gerhard and Bourauel, Christoph},
  title     = {Determination of the frictional coefficient of the implant-antler interface : experimental approach},
  series = {Biomedical Engineering / Biomedizinische Technik},
  volume    = {57},
  journal   = {Biomedical Engineering / Biomedizinische Technik},
  number    = {5},
  publisher = {De Gruyter},
  address   = {Berlin},
  issn      = {1862-278X},
  pages     = {359 -- 363},
  year      = {2012},
  abstract  = {The similar bone structure of reindeer antler to human bone permits studying the osseointegration of dental implants in the jawbone. As the friction is one of the major factors that have a significant influence on the initial stability of immediately loaded dental implants, it is essential to define the frictional coefficient of the implant-antler interface. In this study, the kinetic frictional forces at the implant-antler interface were measured experimentally using an optomechanical setup and a stepping motor controller under different axial loads and sliding velocities. The corresponding mean values of the static and kinetic frictional coefficients were within the range of 0.5-0.7 and 0.3-0.5, respectively. An increase in the frictional forces with increasing applied axial loads was registered. The measurements showed an evidence of a decrease in the magnitude of the frictional coefficient with increasing sliding velocity. The results of this study provide a considerable assessment to clarify the suitable frictional coefficient to be used in the finite element contact analysis of antler specimens.},
  language  = {en}
}
@book{WosnitzaHilgers2012,
  author    = {Wosnitza, Franz and Hilgers, Hans Gerd},
  title     = {Energieeffizienz und Energiemanagement : ein {\"U}berblick heutiger M{\"o}glichkeiten und Notwendigkeiten},
  publisher = {Springer Spektrum},
  address   = {Wiesbaden},
  isbn      = {978-3-8348-1941-3},
  pages     = {XVII, 548 S. : Ill., graph. Darst.},
  year      = {2012},
  language  = {en}
}
@book{JanserHavermann2012,
  author    = {Janser, Frank and Havermann, Marc},
  title     = {Inkompressible Str{\"o}mungen},
  publisher = {Mainz},
  address   = {Aachen},
  isbn      = {978-3-86130-446-3},
  pages     = {189 S. : Ill., graph. Darst.},
  year      = {2012},
  language  = {en}
}
@inproceedings{SchoppNachtrodtHeuermannetal.2012,
  author    = {Schopp, Christoph and Nachtrodt, Frederik and Heuermann, Holger and Scherer, Ulrich W. and Mostacci, Domiziano and Finger, Torsten and Tietsch, Wolfgang},
  title     = {A novel 2.45 GHz/200 W Microwave Plasma Jet for High Temperature Applications above 3600 K},
  series = {Journal of Physics : Conference Series},
  volume    = {406},
  booktitle = {Journal of Physics : Conference Series},
  number    = {012029},
  issn      = {1742-6596},
  pages     = {5},
  year      = {2012},
  language  = {en}
}
@inproceedings{NixFrotscherStaat2012,
  author    = {Nix, Yvonne and Frotscher, Ralf and Staat, Manfred},
  title     = {Implementation of the edge-based smoothed extended finite element method},
  series = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012},
  booktitle = {Proceedings 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012) Vienna, Austria, September 10-14, 2012},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@inproceedings{FrotscherRaatschenStaat2012,
  author    = {Frotscher, Ralf and Raatschen, Hans-J{\"u}rgen and Staat, Manfred},
  title     = {Application of an edge-based smoothed finite element method on geometrically non-linear plates of non-linear material},
  series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@inproceedings{DuongNguyenStaat2012,
  author    = {Duong, Minh Tuan and Nguyen, Nhu Huynh and Staat, Manfred},
  title     = {Numerical stability enhancement of modeling hyperelastic materials},
  series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@inproceedings{TranStaat2012,
  author    = {Tran, Thanh Ngoc and Staat, Manfred},
  title     = {A primal-dual shakedown analysis of 3D structures using the face-based smoothed finite element method},
  series = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  booktitle = {Proceedings European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012)},
  editor    = {Eberhardsteiner, J.},
  year      = {2012},
  language  = {en}
}
@inproceedings{PhamNguyenStaat2012,
  author    = {Pham, Phu Tinh and Nguyen, Thanh Ngoc and Staat, Manfred},
  title     = {FEM based shakedown analysis of hardening structures},
  series = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)},
  booktitle = {Proceedings International Conference on Advances in Computational Mechanics (ACOME)},
  pages     = {870 -- 882},
  year      = {2012},
  language  = {en}
}
@inproceedings{FunkeBoernerKeinzetal.2012,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Keinz, Jan and Kusterer, K. and Kroninger, D. and Kitajima, J. and Kazari, M. and Horikama, A.},
  title     = {Numerical and experimental characterization of low NOx Micromix combustion principle for industrial hydrogen gas turbine applications},
  series = {Proceedings of ASME Turbo Expo 2012},
  booktitle = {Proceedings of ASME Turbo Expo 2012},
  pages     = {11},
  year      = {2012},
  language  = {en}
}
@inproceedings{FunkeBoernerKeinzetal.2012,
  author    = {Funke, Harald and B{\"o}rner, Sebastian and Keinz, Jan and Hendrick, P. and Recker, E.},
  title     = {Low NOx Hydrogen combustion chamber for industrial gas turbine applications", 14th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery},
  series = {ISROMAC-14 : the Forteenth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; Honolulu, Hawaii, February 27 - March 02nd, 2012},
  booktitle = {ISROMAC-14 : the Forteenth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; Honolulu, Hawaii, February 27 - March 02nd, 2012},
  year      = {2012},
  language  = {en}
}
@article{NomdedeuWillenSchiefferetal.2012,
  author    = {Nomdedeu, Mar Monsonis and Willen, Christine and Schieffer, Andre and Arndt, Hartmut},
  title     = {Temperature-dependent ranges of coexistence in a model of a two-prey-one-predator microbial food web},
  series = {Marine Biology},
  volume    = {159},
  journal   = {Marine Biology},
  number    = {11},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-1793},
  doi       = {10.1007/s00227-012-1966-x},
  pages     = {2423 -- 2430},
  year      = {2012},
  abstract  = {The objective of our study was to analyze the effects of temperature on the population dynamics of a three-species food web consisting of two prey bacteria (Pedobacter sp. and Acinetobacter johnsonii) and a protozoan predator (Tetrahymena pyriformis) as model organisms. We assessed the effects of temperature on the growth rates of all three species with the objective of developing a model with four differential equations based on the experimental data. The following hypotheses were tested at a theoretical level: Firstly, temperature changes can affect the dynamic behavior of a system by temperature-dependent parameters and interactions and secondly, food web response to temperature cannot be derived from the single species temperature response. The main outcome of the study is that temperature changes affect the parameter range where coexistence is possible within all three species. This has significant consequences on our ideas regarding the evaluation of effects of global warming.},
  language  = {en}
}
@phdthesis{Schieffer2012,
  author    = {Schieffer, Andre},
  title     = {Studies on diversity and coexistence in an experimental microbial community},
  pages     = {76 Bl. : Ill.},
  year      = {2012},
  abstract  = {Biodiversity and the coexistence of species have puzzled and fascinated biologists since decades and is a hotspot in todays' natural sciences. Preserving this biodiversity is a great challenge as habitats and environments underlying tremendous changes like climate change and the loss of natural habitats, which are mainly due to anthropogenic influences. The coexistence of numerous species even in homogeneous environments is a stunning feature of natural communities and has been summarized under the term 'paradox of plankton'. Up to now, there are several mechanisms discussed, which may contribute to local and global diversity of organisms. Several interspecific trade offs have been identified maintaining the coexistence of species like their abilities regarding competition and predator avoidance, their capability to disperse in space and time, and their ability to exploit variable resources. Further, micro-evolutionary dynamics supporting the coexistence of species have been added to our knowledge, and deriving from theoretical deterministic models, non-linear dynamics which describe the temporal fluctuation of abundances of organisms. Whereas competition and predation seem to be clue structural elements within interacting organisms, the intrinsic dynamic behavior - by means of temporal changes in abundance - plays an important role regarding coexistence within a community. The present work sheds light on different factors affecting the coexistence of species using experimental microbial model systems consisting of a bacterivorous ciliate as the predator and two bacteria strains as prey organism. Additionally, another experimental setup consisting of two up to five bacteria species competing for one limiting resource was investigated. Highly controllable chemostat systems were established to exclude extrinsic disturbances. According to theoretical analyses I was able to show - experimentally and theoretically - that phenotypic plasticity of one species within a microbial one-predator-two-prey food web enlarges the range of possible coexistence of all species under different dynamic conditions, compared to a food web without phenotypic plasticity. This was accompanied by non-linear (chaotic) population dynamics within all experimental systems showing phenotypic plasticity. The experiments on the interplay of competition, predation and invasion showed that all aspects have an influence on species coexistence. Under undisturbed controlled conditions all aspects were analyzed in detail and in combination. Populations showed oscillations which were shown by quasi-chaotic attractors in phase space diagrams. Competition experiments with two up to five bacteria species competing for one limiting resource showed that all organisms were able to coexist which was mediated by species oscillations entering a regime of chaos. Besides that fact it was found, that the productivity (biomass) as well as the total cell numbers - under the same nutrition supply - increased by an increasing number of species in the experimental systems. Up to now, the occurrence of non-linear dynamics in well controlled experimental studies has been recognized several times and this phenomenon seemed to be more common in natural systems than generally assumed.},
  language  = {en}
}
@article{Alexopoulos2012,
  author    = {Alexopoulos, Spiros},
  title     = {Biogas systems: basics, biogas multifunction, principle of fermentation and hybrid application with a solar tower for the treatment of waste animal manure},
  series = {Journal of Engineering Science and Technology Review},
  volume    = {5},
  journal   = {Journal of Engineering Science and Technology Review},
  number    = {4},
  issn      = {1791-2377},
  pages     = {48 -- 55},
  year      = {2012},
  abstract  = {Two of the main environmental problems of today's society are the continuously increasing production of organic wastes as well as the increase of carbon dioxide in the atmosphere and the related green house effect. A way to solve these problems is the production of biogas. Biogas is a combustible gas consisting of methane, carbon dioxide and small amounts of other gases and trace elements. Production of biogas through anaerobic digestion of animal manure and slurries as well as of a wide range of digestible organic wastes and agricultural residues, converts these substrates into electricity and heat and offers a natural fertiliser for agriculture. The microbiological process of decomposition of organic matter, in the absence of oxygen takes place in reactors, called digesters. Biogas can be used as a fuel in a gas turbine or burner and can be used in a hybrid solar tower system offering a solution for waste treatment of agricultural and animal residues. A solar tower system consists of a heliostat field, which concentrates direct solar irradiation on an open volumetric central receiver. The receiver heats up ambient air to temperatures of around 700°C. The hot air's heat energy is transferred to a steam Rankine cycle in a heat recovery steam generator (HRSG). The steam drives a steam turbine, which in turn drives a generator for producing electricity. In order to increase the operational hours of a solar tower power plant, a heat storage system and/ or hybridization may be considered. The advantage of solar-fossil hybrid power plants, compared to solar-only systems, lies in low additional investment costs due to an adaptable solar share and reduced technical and economical risks. On sunny days the hybrid system operates in a solar-only mode with the central receiver and on cloudy days and at night with the gas turbine only. As an alternative to methane gas, environmentally neutral biogas can be used for operating the gas turbine. Hence, the hybrid system is operated to 100\% from renewable energy sources},
  language  = {en}
}
@inproceedings{StreunAlKaddoumParletal.2012,
  author    = {Streun, M. and Al-Kaddoum, R. and Parl, C. and Pietrzyk, U. and Ziemons, Karl and Waasen, S. van},
  title     = {Simulation studies of optical photons in monolithic block scintillators},
  series = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)},
  booktitle = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)},
  publisher = {IEEE},
  address   = {New York},
  isbn      = {978-1-4673-0120-6 (electronic ISBN)},
  doi       = {10.1109/NSSMIC.2011.6154621},
  pages     = {1380 -- 1382},
  year      = {2012},
  abstract  = {The interest in PET detectors with monolithic block scintillators is growing. In order to obtain high spatial resolutions dedicated positioning algorithms are required. But even an ideal algorithm can only deliver information which is provided by the detector. In this simulation study we investigated the light distribution on one surface of cuboid LSO scintillators of different size. Scintillators with a large aspect ratio (small footprint and large height) showed significant position information only for a minimum interaction depth of the gamma particle. The results allow a quantitative estimate for a useful aspect ratio.},
  language  = {en}
}
@inproceedings{FrotscherRaatschenStaat2012,
  author    = {Frotscher, Ralf and Raatschen, Hans-J{\"u}rgen and Staat, Manfred},
  title     = {Effectiveness of the edge-based smoothed finite element method applied to soft biological tissues},
  series = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  booktitle = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  editor    = {Holzapfel, Gerhard A.},
  publisher = {Verlag d. Technischen Universit{\"a}t Graz},
  address   = {Graz},
  isbn      = {978-3-85125-223-1},
  year      = {2012},
  language  = {en}
}
@inproceedings{DuongNguyenStaat2012,
  author    = {Duong, Minh Tuan and Nguyen, Nhu Hunyh and Staat, Manfred},
  title     = {Finite Element Implementation of a 3D Fung-type Model},
  series = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  booktitle = {ESMC-2012 - 8th European Solid Mechanics Conference, Graz, Austria, July 9-13, 2012},
  publisher = {Verlag d. Technischen Universit{\"a}t Graz},
  address   = {Graz},
  isbn      = {978-3-85125-223-1},
  year      = {2012},
  language  = {en}
}