@article{HoetterFateriGebhardt2012,
  author    = {H{\"o}tter, Jan-Steffen and Fateri, Miranda and Gebhardt, Andreas},
  title     = {Selective laser melting of metals: desktop machines open up new chances even for small companies},
  series = {Advanced materials research},
  volume    = {622-623},
  journal   = {Advanced materials research},
  publisher = {Trans Tech Publ.},
  address   = {Baech},
  issn      = {1662-8985 (E-Journal); 1022-6680 (Print)},
  doi       = {10.4028/www.scientific.net/AMR.622-623.461},
  pages     = {461 -- 465},
  year      = {2012},
  abstract  = {Additive manufacturing (AM) of metal parts by using Selective Laser Melting (SLM) has become a powerful tool mostly in the area of automotive, aerospace engineering and others. Especially in the field of dentistry, jewelry and related branches that require individualized or even one-of-a-kind products, the direct digital manufacturing process opens up new ways of design and manufacturing. In these fields, mostly small and medium sized businesses (SME) are operating which do not have sufficient human and economic resources to invest in this technology. But to stay competitive, the application of AM can be regarded as a necessity. In this situation a new desktop machine (Realizer SLM 50) was introduced that cost about 1/3 of a shop floor SLM machine and promises small quality parts. To find out whether the machine really is an alternative for SMEs the University of Applied Science, Aachen, Germany, designed, build and optimized typical parts from the dentistry and the jewelry branches using CoCr and silver material, the latter being new with this application. The paper describes the SLM procedure and how to find and optimize the most important parameters. The test is accompanied by digital simulation in order to verify the build parameters and to plan future builds. The procedure is shown as well as the resulting parts made from CoCr and silver material.},
  language  = {en}
}
@inproceedings{AchenbachGeimerLynenetal.2012,
  author    = {Achenbach, Timm and Geimer, Konstantin and Lynen, Arthur and G{\"o}ttsche, Joachim and Hoffschmidt, Bernhard},
  title     = {Simulation of thermo-mechanical processes in open volumetric absorber modules},
  series = {SolarPaces 2012 : concentrating solar power and chemical energy systems : Sept. 11 - 14 2012, Marrakech, Marokko},
  booktitle = {SolarPaces 2012 : concentrating solar power and chemical energy systems : Sept. 11 - 14 2012, Marrakech, Marokko},
  pages     = {1 -- 8},
  year      = {2012},
  language  = {en}
}
@inproceedings{BungSunMeirelesetal.2012,
  author    = {Bung, Daniel Bernhard and Sun, Q. and Meireles, I. and Matos, J. and Viseu, T.},
  title     = {USBR type III stilling basin performance for steep stepped spillways},
  series = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto},
  booktitle = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto},
  organization    = {International Symposium on Hydraulic Structures <4, 2012, Porto>},
  isbn      = {978-989-8509-01-7},
  pages     = {Elektronisch publiziert},
  year      = {2012},
  language  = {en}
}
@inproceedings{OertelBung2012,
  author    = {Oertel, Mario and Bung, Daniel Bernhard},
  title     = {Characteristics of cross-bar block ramp flows},
  series = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto},
  booktitle = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto},
  organization    = {International Symposium on Hydraulic Structures <4, 2012, Porto>},
  isbn      = {978-989-8509-01-7},
  pages     = {Elektronisch publiziert},
  year      = {2012},
  language  = {en}
}
@inproceedings{Bung2012,
  author    = {Bung, Daniel Bernhard},
  title     = {Sensitivity of phase detection techniques in aerated chute flows to hydraulic design parameters},
  series = {2nd European IAHR congress : 27. - 29. June 2012, M{\"u}nchen},
  booktitle = {2nd European IAHR congress : 27. - 29. June 2012, M{\"u}nchen},
  publisher = {Lehrstuhl u. Versuchsanst. f{\"u}r Wasserbau u. Wasserwirtschaft d. TU M{\"u}nchen},
  address   = {M{\"u}nchen},
  organization    = {International Association for Hydraulic Engineering and Research},
  isbn      = {978-3-943683-03-5},
  pages     = {Artikelkennnummer: B15},
  year      = {2012},
  language  = {en}
}
@inproceedings{SchlurmannBung2012,
  author    = {Schlurmann, Torsten and Bung, Daniel Bernhard},
  title     = {Experimental investigation of flow-induced radial gate vibrations at Lower Subansiri dam},
  series = {Sixth Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : JOINT 2012 : 23.-29.9.2012, Keelung},
  booktitle = {Sixth Chinese-German Joint Symposium on Hydraulic and Ocean Engineering : JOINT 2012 : 23.-29.9.2012, Keelung},
  organization    = {Chinese-German Joint Symposium on Hydraulic and Ocean Engineering <6, 2012, Keelung>},
  pages     = {7 -- 14},
  year      = {2012},
  language  = {en}
}
@article{BoettcherHaselhuhnJakseetal.2012,
  author    = {Boettcher, Martin and Haselhuhn, Angelika and Jakse, Gerhard and Brehmer, Bernhard and Kirschner-Hermanns, Ruth},
  title     = {Overactive bladder syndrome: an underestimated long-term problem after treatment of patients with localized prostate cancer?},
  series = {BJU international},
  volume    = {109},
  journal   = {BJU international},
  number    = {12},
  publisher = {Wiley-Blackwell},
  address   = {Oxford},
  issn      = {1365-2176 (E-Journal); 1464-410X (E-Journal); 0007-1331 (Print); 1464-4096 (Print)},
  doi       = {10.1111/j.1464-410X.2011.10623.x},
  pages     = {1824 -- 1830},
  year      = {2012},
  abstract  = {In this study we observed courses of micturition symptoms and differentiated degrees of symptoms for each point in time while also considering the impact of bothersomeness. Our data show that not only significantly more patients who have undergone BT suffer from OAB than those who have undergone RP, but also that those affected show significantly higher values for severity of OAB symptoms throughout the whole observation period of 36 months. Our data analysis further shows that variability of OAB symptoms as well as fluctuation of severity of OAB symptoms vary to a significantly higher degree after BT than after RP. Looking only at mean figures at a given point in time clearly underestimates the underlying problem. This fact is not reflected in the literature.},
  language  = {en}
}
@article{OertelBung2012,
  author    = {Oertel, Mario and Bung, Daniel Bernhard},
  title     = {Initial stage of two-dimensional dam-break waves: laboratory versus VOF},
  series = {Journal of hydraulic research},
  volume    = {50},
  journal   = {Journal of hydraulic research},
  number    = {1},
  publisher = {Taylor \& Francis},
  address   = {London},
  issn      = {1814-2079 (E-Journal); 0022-1686 (Print)},
  doi       = {10.1080/00221686.2011.639981},
  pages     = {89 -- 97},
  year      = {2012},
  abstract  = {Since several decades, dam-break waves have been of main research interest. Mathematical approaches have been developed by analytical, physical and numerical models within the past 120 years. During the past 10 years, the number of research investigations has increased due to improved measurement techniques as well as significantly increased computer memories and performances. In this context, the present research deals with the initial stage of two-dimensional dam-break waves by comparing physical and numerical model results as well as analytical approaches. High-speed images and resulting particle image velocimetry calculations are thereby compared with the numerical volume-of-fluid (VOF) method, included in the commercial code FLOW-3D. Wave profiles and drag forces on placed obstacles are analysed in detail. Generally, a good agreement between the laboratory and VOF results is found.},
  language  = {en}
}
@article{RibitschHeumannKarletal.2012,
  author    = {Ribitsch, D. and Heumann, S. and Karl, W. and Gerlach, J. and Leber, R. and Birner-Gruenberger, R. and Gruber, K. and Eiteljoerg, I. and Remler, P. and Siegert, Petra and Lange, J. and Maurer, Karl-Heinz and Berg, G. and Guebitz, G. M. and Schwab, H.},
  title     = {Extracellular serine proteases from Stenotrophomonas maltophilia: Screening, isolation and heterologous expression in E. coli},
  series = {Journal of biotechnology},
  volume    = {157},
  journal   = {Journal of biotechnology},
  number    = {1},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1873-4863 (E-Journal); 0168-1656 (Print)},
  doi       = {10.1016/j.jbiotec.2011.09.025},
  pages     = {140 -- 147},
  year      = {2012},
  abstract  = {A large strain collection comprising antagonistic bacteria was screened for novel detergent proteases. Several strains displayed protease activity on agar plates containing skim milk but were inactive in liquid media. Encapsulation of cells in alginate beads induced protease production. Stenotrophomonas maltophilia emerged as best performer under washing conditions. For identification of wash-active proteases, four extracellular serine proteases called StmPr1, StmPr2, StmPr3 and StmPr4 were cloned. StmPr2 and StmPr4 were sufficiently overexpressed in E. coli. Expression of StmPr1 and StmPr3 resulted in unprocessed, insoluble protein. Truncation of most of the C-terminal domain which has been identified by enzyme modeling succeeded in expression of soluble, active StmPr1 but failed in case of StmPr3. From laundry application tests StmPr2 turned out to be a highly wash-active protease at 45 °C. Specific activity of StmPr2 determined with suc-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide as the substrate was 17 ± 2 U/mg. In addition we determined the kinetic parameters and cleavage preferences of protease StmPr2.},
  language  = {en}
}
@article{SchmitzWeber2012,
  author    = {Schmitz, Philipp and Weber, Martin},
  title     = {Buying and selling behavior of individual investors in option-like securities},
  series = {Die Betriebswirtschaft : DBW},
  volume    = {72},
  journal   = {Die Betriebswirtschaft : DBW},
  number    = {5},
  publisher = {Sch{\"a}ffer-Poeschel},
  address   = {Stuttgart},
  issn      = {0342-7064},
  doi       = {10.2139/ssrn.2055088},
  pages     = {409 -- 426},
  year      = {2012},
  abstract  = {We analyze the trading behavior of individual investors in option-like securities, namely bankissued warrants, and thus expand the growing literature of investors behavior to a new kind of securities. A unique data set from a large German discount broker gives us the opportunity to analyze the trading behavior of 1,454 investors, making 89,958 transactions in 6,724 warrants on 397 underlyings. In different logit regression, we make use of the facts that investors can speculate on rising and falling prices of the underlying with call and put warrants and that we also have information about the stock portfolios of the investors. We report several facts about the trading behavior of individual investors in warrants that are consistent with the literature on the behavior of individual investors in the stock market. The warrant investors buy calls and sell puts if the price of the underlying has decreased over the past trading days and they sell calls and buy puts if the price of the underlying has increased. That means, the investors follow negative feedback trading strategies in all four trading categories observed. In addition, we find strong evidence for the disposition effect for call as well as put warrants, which is reversed in December. The trading behavior is also influenced if the underlying reaches some exceptionally prices, e.g. highs, lows or the strike price. We show that hedging, as one natural candidate to buy puts, does not play an important role in the market for bank-issued warrants.},
  language  = {en}
}
@article{LeidingerNoistenWollert2012,
  author    = {Leidinger, Rafael and Noisten, Thomas and Wollert, J{\"o}rg},
  title     = {Realtime automation networks in moVing industrial environments},
  series = {Journal of systemics, cybernetics and informatics},
  volume    = {Vol. 10},
  journal   = {Journal of systemics, cybernetics and informatics},
  number    = {Iss. 2},
  publisher = {IIIC},
  address   = {Orlando},
  issn      = {1690-4532},
  pages     = {52 -- 56},
  year      = {2012},
  abstract  = {The radio-based wireless data communication has made the realization of new technical solutions possible in many fields of the automation technology (AT). For about ten years, a constant disproportionate growth of wireless technologies can be observed in the automation technology. However, it shows that especially for the AT, conventional technologies of office automation are unsuitable and/or not manageable. The employment of mobile services in the industrial automation technology has the potential of significant cost and time savings. This leads to an increased productivity in various fields of the AT, for example in the factory and process automation or in production logistics. In this paper technologies and solutions for an automation-suited supply of mobile wireless services will be introduced under the criteria of real time suitability, IT-security and service orientation. Emphasis will be put on the investigation and development of wireless convergence layers for different radio technologies, on the central provision of support services for an easy-to-use, central, backup enabled management of combined wired / wireless networks and on the study on integrability in a Profinet real-time Ethernet network.},
  language  = {en}
}
@inproceedings{Wollert2012,
  author    = {Wollert, J{\"o}rg},
  title     = {The performance of UWB-communication in an industrial environment},
  series = {IEEE 1st International Symposium on Wireless Systems : (IDAACS-SWS) : Offenburg, 20-21 Sept. 2012},
  booktitle = {IEEE 1st International Symposium on Wireless Systems : (IDAACS-SWS) : Offenburg, 20-21 Sept. 2012},
  publisher = {IEEE},
  address   = {Piscataway, NJ},
  organization    = {International Symposium on Wireless Systems <1, 2012, Offenburg>},
  isbn      = {978-1-4673-4678-8},
  doi       = {10.1109/IDAACS-SWS.2012.6377639},
  pages     = {85 -- 90},
  year      = {2012},
  language  = {en}
}
@article{MottaghyDijkshoorn2012,
  author    = {Mottaghy, Darius and Dijkshoorn, Lydia},
  title     = {Implementing an effective finite difference formulation for borehole heat exchangers into a heat and mass transport code},
  series = {Renewable Energy},
  volume    = {45},
  journal   = {Renewable Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0960-1481},
  doi       = {10.1016/j.renene.2012.02.013},
  pages     = {59 -- 71},
  year      = {2012},
  abstract  = {We present an effective finite difference formulation for implementing and modeling multiple borehole heat exchangers (BHE) in the general 3-D coupled heat and flow transport code SHEMAT. The BHE with arbitrary length can be either coaxial or double U-shaped. It is particularly suitable for modeling deep BHEs which contain varying pipe diameters and materials. Usually, in numerical simulations, a fine discretization of the BHE assemblage is required, due to the large geometric aspect ratios involved. This yields large models and long simulation times. The approach avoids this problem by considering heat transport between fluid and the soil through pipes and grout via thermal resistances. Therefore, the simulation time can be significantly reduced. The coupling with SHEMAT is realized by introducing an effective heat generation. Due to this connection, it is possible to consider heterogeneous geological models, as well as the influence of groundwater flow. This is particularly interesting when studying the long term behavior of a single BHE or a BHE field. Heating and cooling loads can enter the model with an arbitrary interval, e.g. from hourly to monthly values. When dealing with large BHE fields, computing times can be further significantly reduced by focusing on the temperature field around the BHEs, without explicitly modeling inlet and outlet temperatures. This allows to determine the possible migration of cold and warm plumes due to groundwater flow, which is of particular importance in urban areas with a high BHE installation density. The model is validated against the existing BHE modeling codes EWS and EED. A comparison with monitoring data from a deep BHE in Switzerland shows a good agreement. Synthetic examples demonstrate the field of application of this model.},
  language  = {en}
}
@inproceedings{DachwaldFeldmannEspeetal.2012,
  author    = {Dachwald, Bernd and Feldmann, Marco and Espe, Clemens and Plescher, Engelbert and Konstantinidis, K. and Forstner, R.},
  title     = {Enceladus explorer - A maneuverable subsurface probe for autonomous navigation through deep ice},
  series = {63rd International Astronautical Congress 2012, IAC 2012; Naples; Italy; 1 October 2012 through 5 October 2012. (Proceedings of the International Astronautical Congress, IAC ; 3)},
  booktitle = {63rd International Astronautical Congress 2012, IAC 2012; Naples; Italy; 1 October 2012 through 5 October 2012. (Proceedings of the International Astronautical Congress, IAC ; 3)},
  publisher = {Curran},
  address   = {Red Hook, NY},
  organization    = {International Astronautical Congress <63, 2012, Napoli>},
  isbn      = {978-1-62276-979-7},
  pages     = {1756 -- 1766},
  year      = {2012},
  language  = {en}
}
@inproceedings{KernSchelthoffMathieu2012,
  author    = {Kern, Alexander and Schelthoff, Christof and Mathieu, Moritz},
  title     = {Calculation of interception efficiencies for mesh-type air-terminations according to IEC 62305-3 using a dynamic electro-geometrical model},
  series = {International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna},
  booktitle = {International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna},
  publisher = {IEEE},
  address   = {Piscataway, NJ},
  organization    = {International Conference on Lightning Protection <2012, Wien>},
  isbn      = {978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print)},
  pages     = {1 -- 6},
  year      = {2012},
  language  = {en}
}
@inproceedings{LoPiparoKernMazzetti2012,
  author    = {Lo Piparo, G. B. and Kern, Alexander and Mazzetti, C.},
  title     = {Some masterpoints about risk due to lightning},
  series = {International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna},
  booktitle = {International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna},
  publisher = {IEEE},
  address   = {Piscataway, NJ},
  organization    = {International Conference on Lightning Protection <2012, Wien>},
  isbn      = {978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print)},
  pages     = {1 -- 6},
  year      = {2012},
  language  = {en}
}
@article{BragardvanHoekDeDoncker2012,
  author    = {Bragard, Michael and van Hoek, H. and De Doncker, R. W.},
  title     = {A major design step in IETO concept realization that allows overcurrent protection and pushes limits of switching performance},
  series = {IEEE transactions on power electronics},
  volume    = {27},
  journal   = {IEEE transactions on power electronics},
  number    = {9},
  publisher = {IEEE},
  address   = {New York},
  issn      = {0885-8993},
  doi       = {10.1109/TPEL.2012.2189136},
  pages     = {4163 -- 4171},
  year      = {2012},
  abstract  = {This paper presents the latest prototype of the integrated emitter turn-off thyristor concept, which potentially ranks among thyristor high-power devices like the gate turn-off thyristor and the integrated gate-commutated thyristor (IGCT). Due to modifications of the external driver stage and mechanical press-pack design optimization, this prototype allows for full device characterization. The turn-off capability was increased to 1600 A with an active silicon area of 823mm2 . This leads to a transient peak power of 672.1kW/cm² . Within this paper, measurements and concept assessment are presented and a comparison to state-of-the-art IGCT devices is provided.},
  language  = {en}
}
@phdthesis{Bragard2012,
  author    = {Bragard, Michael},
  title     = {The integrated emitter turn-off thyristor : an innovative MOS-gated high-power device. - (Aachener Beitr{\"a}ge des ISEA ; 62)},
  publisher = {Shaker},
  address   = {Aachen},
  isbn      = {978-3-8440-1152-4},
  pages     = {III, 164 S. : Ill., graph. Darst.},
  year      = {2012},
  abstract  = {This thesis introduces the Integrated Emitter Turn-Off (IETO) Thyristor as a new high-power device. Known state-of-the-art research activities like the Dual GCT, the ETO thyristor and the ICT were presented and critically reviewed. A comparison with commercialized solutions identifies the pros and cons of each type of device family. Based on this analysis, the IETO structure is proposed, covering most benefits of each device class. In particular the combination of a MOS-assisted turn-off with a thyristor-based device allows a voltage-controlled MOS switching and the low on-state voltage of the thyristors. The following synthesis of an IETO device stands on a three-dimensional field of optimization spanned by electric, mechanical and thermal aspects. From an electric point of view, the lowest possible parasitic inductance and resistance within the commutation path are optimization criteria. The mechanical construction has to withstand the required contact pressure of multiple kilo Newtons. Finally, thermal borders limit the maximum average current of the device. FEM simulations covering these three aspects are performed for several design proposals. An IETO prototype is constructed and measurements on various test benches attest thermal, mechanical and electric performance. A local decoupling of the external driver stage and the presspack housing is presented by a cable connection. This separation enables a thermal and mechanical independence, which is advantageous in terms of vibrations and thermal cycles including increased reliability. The electric pulse performance of the prototype device is a factor of 3.1 above today''s solutions. In single-pulse measurements, a current up to 1600 A was successfully turned off at 115°C with an active silicon area of 823 mm². One reason for this increased turn-off capability is the extremely low-inductive construction. Additional functionality of the IETO thyristor like over-current self-protection and defined short-circuit failure state are successfully verified.},
  language  = {en}
}
@inproceedings{NoetzoldUphuesWegeneretal.2012,
  author    = {N{\"o}tzold, K. and Uphues, A. and Wegener, R. and Soter, S. and Fink, K. and Bragard, Michael and Griessel, R.},
  title     = {Inverter based test setup for LVRT verification of a full-scale 2 MW wind power converter},
  series = {EPE Joint Wind Energy and T\&D Chapters Seminar : 28th and 29th of June 2012, in the Utzon Centre, Aalborg, Denmark ; papers, posters, presentations. - Session 2: Grid connection, compliance},
  booktitle = {EPE Joint Wind Energy and T\&D Chapters Seminar : 28th and 29th of June 2012, in the Utzon Centre, Aalborg, Denmark ; papers, posters, presentations. - Session 2: Grid connection, compliance},
  publisher = {EPE Association},
  address   = {Brussels},
  year      = {2012},
  language  = {en}
}
@article{EilmannRigling2012,
  author    = {Eilmann, Britta and Rigling, Andreas},
  title     = {Tree-growth analyses to estimate tree species' drought tolerance},
  series = {Tree Physiology},
  volume    = {32},
  journal   = {Tree Physiology},
  number    = {2},
  editor    = {Abrams, Marc},
  publisher = {Oxford University Press},
  address   = {Oxford},
  issn      = {0829-318X (Print)},
  doi       = {10.1093/treephys/tps004},
  pages     = {178 -- 187},
  year      = {2012},
  abstract  = {Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species.},
  language  = {en}
}